Wouldn't it be cheaper if you supply your own parts such as oil, etc and get the garage to just do the labour?
Or would you guys recommend just paying everything to the garage? As I know they must make a fair mark-up from e.g what oil costs wholesale or from suppliers. The only issue I think this may cause, is if you have a warranty or if you sell the car, as some people may not like it for some odd reason (even though you would have the receipts for oil, filters, belts etc). I don't think the garage would particularly like it too... what do you guys do?
