ReadableNumber.php

<?php

namespace App\Casts;

use Illuminate\Contracts\Database\Eloquent\CastsAttributes;

class ReadableNumber implements CastsAttributes
{
    /**
     * Prepare the given value for storage.
     *
     * @param  \Illuminate\Database\Eloquent\Model  $model
     * @param  string  $key
     * @param  array  $value
     * @param  array  $attributes
     * @return string
     */
    public function get($model, $key, $value, $attributes)
    {
        return (isset($value) ? number_format($value, 2, ',', ' ') : null); 
    }

    public function set($model, $key, $value, $attributes)
    {
        return [ $key => str_replace(" ", "", str_replace(",", ".", $value)) ];
    }
}

Usage in model:

    /**
     * The attributes that should be cast to native types.
     *
     * @var array
     */
    protected $casts = [
        'price' => ReadableNumber::class
    ];

In your migration :

$table->decimal('price', 12, 2)->default(0);