Code

garage_Car.java

package garage;
public class Car {
    String carName;
    String carModel;
    String status;
    String color;
    int value;
    boolean sold;

    /**
     * getters and setters for all the car attributes
     * @return
     */
    public boolean isSold() {
        return sold;
    }

    public void setSold(boolean sold) {
        this.sold = sold;
    }

    public int getValue() {
        return value;
    }

    public String getCarName() {
        return carName;
    }

    public String getCarModel() {
        return carModel;
    }

    public String getStatus() {
        return status;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public String getColor() {
        return color;
    }

    /**
     * constructor
     * @param carName
     * @param carModel
     * @param color
     * @param status
     * @param value
     * @param sold
     */
    public Car(String carName, String carModel, String color, String status, int value, boolean sold){
        this.carName = carName;
        this.carModel = carModel;
        this.color = color;
        this.status = status;
        this.value = value;
        this.sold = sold;
    }

}

garage_CarListOutput.java

package garage;

import java.util.ArrayList;

public class CarListOutput {
    /**
     * Formated output for the "repair car" list output.
     * @param carList
     */
    public void brokenCarListOutput(ArrayList<Car> carList){
        System.out.println("The following cars are registered as broken:");
        System.out.format("%20s %20s %20s %20s %20s %20s %20s", "Car Number", "Car Name", "Car Model", "Car Color", "Car Status", "Car Value", "Sold");
        System.out.println();
        System.out.println("---------------------------------------------------------------------------------------------------------------------------------------------------");
        for(int i = 0; i < carList.size(); i++) {
            if(carList.get(i).getStatus().toLowerCase().equals("broken")){
                String valueString = String.valueOf(carList.get(i).getValue());
                String soldString = "";
                if(carList.get(i).isSold()){
                    soldString = "Yes";
                }
                else if(!carList.get(i).isSold()){
                    soldString = "No";
                }
                System.out.format("%20d %20s %20s %20s %20s %20s %20s",
                        i, carList.get(i).getCarName(), carList.get(i).getCarModel(), carList.get(i).getColor(), carList.get(i).getStatus(), valueString, soldString);
            }
            System.out.println();
        }
        System.out.println("---------------------------------------------------------------------------------------------------------------------------------------------------");
        System.out.println("Which one do you want to repair? (enter car number):");
    }

    /**
     * Formated output for the "sell car" list.
     * @param carList
     */
    public void unsoldCarListOutput(ArrayList<Car> carList){
        System.out.println("The following cars are registered as unsold:");
        System.out.format("%20s %20s %20s %20s %20s %20s %20s", "Car Number", "Car Name", "Car Model", "Car Color", "Car Status", "Car Value", "Sold");
        System.out.println();
        System.out.println("---------------------------------------------------------------------------------------------------------------------------------------------------");
        for(int i = 0; i < carList.size(); i++) {
            if(!carList.get(i).isSold()){
                String valueString = String.valueOf(carList.get(i).getValue());
                String soldString = "";
                if(carList.get(i).isSold()){
                    soldString = "Yes";
                }
                else if(!carList.get(i).isSold()) {
                    soldString = "No";
                }
                System.out.format("%20d %20s %20s %20s %20s %20s %20s",
                        i, carList.get(i).getCarName(), carList.get(i).getCarModel(), carList.get(i).getColor(), carList.get(i).getStatus(), valueString, soldString);
                System.out.println();
            }
        }
        System.out.println("---------------------------------------------------------------------------------------------------------------------------------------------------");
        System.out.println("Which one do you want to sell? (enter car number):");
    }

    /**
     * Formated output for the "display cars" list. 
     * @param carList
     */

    public void regularCarListOutput(ArrayList<Car> carList){
        System.out.format("%20s %20s %20s %20s %20s %20s %20s", "Car Number", "Car Name", "Car Model", "Car Color", "Car Status", "Car Value", "Sold");
        System.out.println();
        System.out.println("---------------------------------------------------------------------------------------------------------------------------------------------------");
        for (int i = 0; i < carList.size(); i++) {
            String valueString = String.valueOf(carList.get(i).getValue());
            String soldString = "";
            if(carList.get(i).isSold()){
                soldString = "Yes";
            }
            else if(!carList.get(i).isSold()){
                soldString = "No";
            }
            System.out.format("%20d %20s %20s %20s %20s %20s %20s",
                    i, carList.get(i).getCarName(), carList.get(i).getCarModel(), carList.get(i).getColor(), carList.get(i).getStatus(), valueString, soldString);
            System.out.println();
        }
        System.out.println("---------------------------------------------------------------------------------------------------------------------------------------------------");
    }
}

garage_ChangeCarAttribute.java

package garage;

import java.util.ArrayList;

public class ChangeCarAttribute {

    /**
     * Check for every slot in carlist if the control variable matches the choice from the user, and if the slot of the
     * arraylist at the index of the control variable is not null, set status to repaired.
     * @param carList
     * @param choice
     */
    public void repair(ArrayList<Car> carList, int choice){
        for(int i = 0; i < carList.size(); i++) {
            if(i == choice && carList.get(i) != null) {
                carList.get(i).setStatus("repaired");
                try {
                    System.out.println("Repairing car " + carList.get(i).carName + " " + carList.get(i).carModel);
                    Thread.sleep(1000);
                    System.out.println("The car is now repaired.");
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
            else{
                System.out.println("Invalid car number.");
            }
        }
    }

    /**
     * method used to change the attribute "sold" from yes to no.
     * @param carList
     * @param bankAccount
     * @param choice
     */
    public void sell(ArrayList<Car> carList, Money bankAccount, int choice){
        for(int i = 0; i < carList.size(); i++){
           if(i == choice && carList.get(i) != null) {
               carList.get(i).setSold(true);
               try {
                   System.out.println("Selling car " + carList.get(i).carName + " " + carList.get(i).carModel);
                   Thread.sleep(2000);
                   bankAccount.setBankAccount(carList.get(i).getValue());
               } catch (InterruptedException e) {
                   e.printStackTrace();
               }
           }
           else{
               System.out.println("Invalid car number.");
           }
        }
    }

    /**
     * method delete is used to actually delete the car from the list.
     * @param carList
     * @param choice
     */
    public void delete(ArrayList<Car> carList, int choice){
        for(int i = 0; i < carList.size(); i++){
            if(i == choice && carList.get(i) != null){
                try{
                    System.out.println("Deleting car " + carList.get(i).carName + " " + carList.get(i).carModel);
                    Thread.sleep(1000);
                }
                catch(InterruptedException e){
                    e.printStackTrace();
                }
                carList.remove(i);
            }
            else{
                System.out.println("Invalid car number.");
            }
        }
    }

}

garage_ClearScreen.java

package garage;

/**
 * Used to clear the screen.
 */
public class ClearScreen {
    public static void clearScreen() {

        for(int i = 0; i < 50000; i++){
            System.out.println();
        }

    }
}

garage_InputOutput.java

package garage;

import java.util.Scanner;

/**
 * Input for normal Strings. This is used for reading the car attributes.
 */
public class InputOutput {
    private String input;
    Scanner sc = new Scanner(System.in);
    public String inputManager() {
        input = sc.nextLine();
        return input;
    }

    /**
     * Input for number.
     * checking if the first read input string contains chars other than numbers. if so, ask the user to enter a number.
     */
    private int inputNumber;
    private String inputNumberString;
    Scanner scNumber = new Scanner(System.in);
    public int inputManagerNumber(int tempNumber) {
        while (tempNumber == 0){
            inputNumberString = scNumber.nextLine();
            if(inputNumberString.matches("[a-zA-Z]+")){
                System.out.println("Please enter a number:");
            }
            else{
                inputNumber = Integer.parseInt(inputNumberString);
                tempNumber = 1;
            }
        }
        return inputNumber;
    }

    /**
     * Special Scanner for the car attribute "Status" this is needed because the Status needs to be
     * "broken" or "repaired".
     */
    private String inputBroken;
    Scanner scBroken = new Scanner(System.in);
    public String inputManagerBroken(int tempBroken) {
        while (tempBroken == 0){
            inputBroken = scBroken.nextLine();
            if(inputBroken.toLowerCase().equals("broken")){
                tempBroken = 1;
            }
            else if(inputBroken.toLowerCase().equals("repaired")){
                tempBroken = 1;
            }
            else{
                System.out.println("Please enter valid input: 'broken' or 'repaired'");
                tempBroken = 0;
            }
        }
        return inputBroken;
    }


    /**
     * Separate scanner for the car attribute "sold". Because the user writes "yes" or "no", this is needed to even set
     * the boolean value.
     */
    private boolean inputBool;
    private String inputBoolString;
    Scanner scBool = new Scanner(System.in);
    public boolean inputManagerBool(int tempBool) {
       while(tempBool == 0) {
           inputBoolString = scBool.nextLine();
           if (inputBoolString.toLowerCase().equals("yes")) {
               inputBool = true;
               tempBool = 1;
           } else if (inputBoolString.toLowerCase().equals("no")) {
               inputBool = false;
               tempBool = 1;
           } else {
               System.out.println("Please enter 'yes' or 'no'");
           }
       }
        return inputBool;
    }


}

garage_main.java

package garage;

import java.util.ArrayList;

public class main {

    /**
     * Creating arraylist and array.
     * ArrayList "carList" is where the whole cars will be saved.
     * Array "carAttributes" is where the individual attributes will be saved (name, color etc.)
     */
    private static ArrayList<Car> carList = new ArrayList<>();
    private static String[] carAttributes = new String[4];

    public static void main(String [ ] args){
        /**
         * Creating the objects which will be needed throughout the program.
          */
        ClearScreen screen = new ClearScreen();
        InputOutput menuInput = new InputOutput();
        InputOutput inputOutput = new InputOutput();
        CarListOutput listOutput = new CarListOutput();
        Money bankAccountOne = new Money();
        ChangeCarAttribute changeCar = new ChangeCarAttribute();

        /**
         * clearing the screen once for a normal output.
         * getting user input which will be needed to determine the following action.
         * boolean "close" is needed to shut down the program if wanted.
         */
        screen.clearScreen();
        System.out.println("What you want to do? (type 'help' for a menu list):");
        String menuInputString = menuInput.inputManager();
        boolean close = false;


        do {
            if (menuInputString.toLowerCase().equals("new car")) {

                /**
                 * asking for the car attributes and saving the user input
                 * creating "value" and "sold". These are attributes needed to create the car
                 */
                int value;
                boolean sold;
                System.out.println("Name:");
                carAttributes[0] = inputOutput.inputManager();

                System.out.println("Model:");
                carAttributes[1] = inputOutput.inputManager();

                System.out.println("Color:");
                carAttributes[2] = inputOutput.inputManager();

                System.out.println("Status:");
                carAttributes[3] = inputOutput.inputManagerBroken(0);

                System.out.println("Value (in $):");
                value = inputOutput.inputManagerNumber(0);

                System.out.println("Sold (Yes or No):");
                sold = inputOutput.inputManagerBool(0);
                /**
                 * Adding new slot to the arraylist "carList". Filling the slot with a newly created object "Car".
                 * "Car" contains the attributes saved in the array "carAttributes" in addition to the variables "value"
                 * and "sold"
                 */
                carList.add(new Car(carAttributes[0], carAttributes[1], carAttributes[2], carAttributes[3], value, sold));
                System.out.println("New Car added to garage.");
            }

            else if (menuInputString.toLowerCase().equals("display cars")) {
                /**
                 * using method "regularCarListOutput" which creates a normal output of the cars in the arrayList "carList"
                 * with all their attributes.
                 */
                if(carList.size() > 0){
                    listOutput.regularCarListOutput(carList);
                }
                else{
                    System.out.println("No cars to display.");
                }
            }

            else if (menuInputString.toLowerCase().equals("repair car")) {
                /**
                 * create a output of the cars which have set the attribute "Status" to "broken".
                 * integer "choice" is needed by the method "repair". "choice" will determine which car, if wanted, will be repaired.
                 */
                if(carList.size() > 0) {
                    int choice;
                    listOutput.brokenCarListOutput(carList);
                    choice = inputOutput.inputManagerNumber(0);
                    changeCar.repair(carList, choice);
                }
                else{
                    System.out.println("No cars are broken.");
                }
            }
             else if(menuInputString.toLowerCase().equals("sell car")){
                /**
                 * First, check if the carList even contains any cars which could be sold. If not, print out that there
                 * are no cars available.
                 * Output a list of the cars with the attribute "Sold" will be printed.
                 * Attribute "Sold" will be changed from no to yes in the chosen car.
                 */
                if(carList.size() > 0) {
                        listOutput.unsoldCarListOutput(carList);
                        int choice = inputOutput.inputManagerNumber(0);
                        changeCar.sell(carList, bankAccountOne, choice);
                }
                else{
                    System.out.println("No cars available to sell");
                }
             }
             else if(menuInputString.toLowerCase().equals("help")){
                /**
                 * Help list outpout
                 */
                System.out.println("Here is a list of the possible commands with a short description:");
                System.out.println("New car (creates a new car)");
                System.out.println("Display cars (displays a list of all the cars)");
                System.out.println("Repair car (displays a list of the broken cars and lets you repair one)");
                System.out.println("Sell car (displays a list of the unsold cars and lets you sell one)");
                System.out.println("Delete car (delete a car out of the list)");
                System.out.println("Get money (display your money)");
                System.out.println("Close (exits the program)");
            }
             else if(menuInputString.toLowerCase().equals("get money")){
                /**
                 * getBankAccount prints out the current money available
                 */
                 System.out.println("You have " + bankAccountOne.getBankAccount() + "$");
            }
            else if(menuInputString.toLowerCase().equals("delete car")){
                /**
                 * Check if there are any cars in arraylist carlist. if so, print out a list of all the cars in the program.
                 * choice is the input which determines the car that will be deleted.
                 */
                if(carList.size() > 0) {
                    listOutput.regularCarListOutput(carList);
                    System.out.println("Which car do you want to delete?");
                    int choice = inputOutput.inputManagerNumber(0);
                    changeCar.delete(carList, choice);
                }
                else{
                    System.out.println("No cars available to delete");
                }
            }
            else{
                System.out.println("Unknown command. Type 'help' for a list of the available commands");
            }
            System.out.println("What you want to do? (type 'help' for a menu list):");
            menuInputString = inputOutput.inputManager();
            screen.clearScreen();
            if(menuInputString.toLowerCase().equals("close")){
                close = true;
            }

        }while (close == false);
    }
}

garage_Money.java

package garage;

public class Money {
    /**
     * getters and setters for the bank account. bank account is used to display the money.
     * @return
     */
    public int getBankAccount() {
        return bankAccount;
    }
    public void setBankAccount(int bankAccount) {
        this.bankAccount = getBankAccount() + bankAccount;
    }
    int bankAccount;
}

Ciao homie