After sales service is horrific, don't ever buy a car from here

The car is faulty, they say they can fix it, a booking is made at the workshop, they don't pay the workshop after the car is fixed, now the workshop won't release the car. It's day two now and I'm still waiting and the workshop won't release the car because they haven't received a proof of payment from WeBuyCars. What horrible business is this? Am I supposed to remain stranded without a car?