Laravel 5.1 Eloquent add conditions

I have a problem.

Car.php

class Car extends Model {
    protected $table = 'master_cars';
}

Person.php

class Person extends Model {
    protected $table = 'master_persons';

    public function car() {
        return $this->belongsTo('App\Models\Car', 'car_id', 'id');
    }
}

Controller.php

$cars = Car::orderBy('id', 'desc')->where('name', '=', $request->name);

if (!empty($request->person)) {
    $cars->join('master_persons', 'master_persons.car_id', '=', 'master_cars.id')
     ->where('master_persons.name', '=', $request->person);
}
$cars->paginate(10);

return view('main.index')
            ->with('cars', $cars);

index.blade.php

@foreach ($cars as $car)
    {!! car->name !!}
@endforeach
{!! $cars->render() !!}

In this way, when you use the Eloquent, the following error occurs.

"Call to undefined method Illuminate\Database\Query\Builder::render() "

Resolution is or not people can be seen?

via Chebli Mohamed