Engine repair on Audi 1.8 Auto 1998

I recently took my Audi 1.8 Auto 1998 (R Reg 130000K Mileage ) in for a interim Oil service at a nationwide autocentre (NB the car had a major service by them only 4 months ago at 120000K and no real probs were noted at the time) and was advised that when they received the car there was v little oil in the engine and that as a result the engine had suffered. They said that although they had managed to reduce the amount of noise coming from the cam belt; the engine/cam belt still appeared to sound too loud and that it appeared to be leaking oil (Although they could not tell where from). They also said there may be a electrical engine fault as they said it appeared to be lacking in power and the throttle appeared to be slightly slow to respond. They said it is probably not worth carrying out the repairs as the work would be too expensive and involve a lot of work.

What i am wondering now is whether it would be worth geting a second opinion and quote from a garage that deals with Audi/VAG engine repair.

What does everyone else think? Would i just be better of just cutting my losses and just keep topping up/regularly monitoring the oil and wait for the engine just to die on me or is it worth getting repaired (According to the the garage the only problem with the car is the engine; all else is ok).

Does anyone have a rough idea of what the engione repairs costs could be in the region of?

Any recommendations for any good Audi/VAG garages that specialise in engine repair ,close to the east london/essex border .

Regards Dr pants