I am in the process of buying a 1 owner, 67,000 warranted 80 avant tdi auto. It has been stood for a while so needs some recommissioning. But overall, its nice. Could anybody tell me what should this do to the gallon, bearing in mind its an auto. How do the figures differ between heavy and light driving? Also, what should the value of this 1994 car be? Also, is air conditioning difficult to fit retrospectively. What would it cost to do that? Who could do it? Sorry for all the quesitons but any help would be gratefully accepted.