Let's see. You want to sell your current, paid off and rare Coupe. Probably
get 6 to 8,000 for it. Then use that as a DP on a $30,000 A4. Which means
you'll have to finance/lease it for around 400$/month.
In three months of leasing costs, you've just spent the same amt that you
could've to make the coupe "perfect". Then in the next 3 months, you could
get Eric's advice and upgrade the suspension and the car would be even
better. I belive you have the four-valve heads/non turbo, so I don't know
what you could do to improve the engine-but I think your coupe is much
quicker than the A-4; doesn't it do 0-60 in around 7.5 sec.? Pretty fast to
me. And the leather is the same quality in both cars.
Why don't you spend the cash on your coupe and make it your dream project
car? When it does finally crap out in say 80,000 miles, then trade it in on
either a used A-4 (with five valve heads), S-4 (better yet) or the next
miracle that Audi produces.
I still have withdrawal pains from trading (more like sacrificing) my '86
coupe for my '89 TQW.