considering purchase of '88 model 80 quattro - any warnings/advice?

[davidder@teleport.com (David R. Derting)]

Yesterday we (spouse and self) found a used '88 model 80 quattro w/ 65K
miles.  The car appears to be in good shape - good paint, tires, exhaust
system, solid suspension, lots of brake disk left, no oil leaks from the
engine or trans areas.  I've not done a compression test or had a leak-down
test done yet - that will be one of the final criteria to do the deal.  BTW
- the ask price is 'round $7k.

Can anyone suggest weak points of this year and model that I should be aware of?

Thanks in advance
David