Very possible but when £10,000 of your own money is riding on it, what are you going to do? Tell the captain "no"?
The system of paying for hour building on commercial aircraft needs to stop! It means constant low experience in the RHS, unfair completion between proper airlines (due to massively reduced wage bills), potential new pilots being put off by the constant "raising of the financial bar" and erosion to professional pilot's T+C's.
It IS a safety concern!