gistfile1.ps1

# Installs the AzureRM PowerShell module from the PSGallery
Install-Module AzureRM -force
# Logs you in to Azure
Login-AzureRmAccount
# Gets your Azure subscription then selects it which essentially logs you in to it. Needs to be done if your account has access
# to multiple subscription
Get-AzureRmSubscription -SubscriptionName "enter your subscription name" | Select-AzureRmSubscription
# Gets a list of all the Azure VM's in your subscription
$vms = Get-AzureRmVM
# Initializes a empty variable for $details to give it the ability to add more than one item easily
$details = @()
# Foreach loop for all of the VM's in $vms
foreach ($vm in $vms)
{
    # Get's a list of all of the available instance sizes for the particular VM but filters it out to match the one the VM is currently using
    # to get CPU and Memory specs
    $vmsize = Get-AzureRmVMSize -VMName $vm.Name -ResourceGroupName $vm.ResourceGroupName | ? {$_.Name -eq $vm.HardwareProfile.VmSize} 
    # Creates a custom PowerShell object to format the information and take values from both the $vm variable and $vmsize variable
    # and for each one of the VM's in the $vms loop it will append it to $details
    $details += New-Object -TypeName PSObject -Property @{
        ResourceGroup = $vm.ResourceGroupName
        Name          = $vm.Name
        Location      = $vm.Location
        VMSize        = $vmsize.Name
        CPU           = $vmsize.NumberOfCores
        Memory        = $vmsize.MemoryInMB
        OsType        = $vm.StorageProfile.ImageReference.Sku
    } 
}

# Outputs all of $details to a grid window. Did this for the example but this can be a CSV or JSON file etc
$details | Out-GridView