I have always been told by our finance rep that the finance is down to the customer, it's great that your trying to help him out of the deal, but ultimately he needs to settle the finance before he brings the vehicle back, I don't see a way out of the deal, particularly if his trade in had finance on and now it doesn't, you can offer him a full refund, but he needs to pay off the finance with a personal loan before trading, so it is clear of finance, then you pay him, give him his car back and the difference is what he pays off his personal finance. The guy is being unreasonbable assuming you will get him out of a deal for a repairable fault, so i would point out the complexitiy of returning a vehicle he doesn't own and the cost implications he will be liable for to the finance companies and let him make the judgement about whether a repair is the cheapest and easiest option!! With regard to SOGA and their car, you are just returning their goods, its not a sale...