After service damager

I took my classic 2002 vehicle to VIP Detailing in Hartbee****rt for ceramic coating. I had to pay full amount in advance before they would start. From there the completion date kept moving out and eventually on completion the Immobilier & central locking were not working. The owner said he received it like that. After loads of back and forth, he said he will fix it, however I have to drive 150km to the place where he is willing to fix it. I suggest you don't take any classic cars here and if so, only pay after you receive your car and no damages.