I have a Audi S4 and love the car in the summer and winter, I dont know if you can afford a S4 but a A4 Avant (wagon) has plenty of power and handles great. As for repairs I do it all my self makes it way cheaper and is not to hard if you can know a little about cars.
HAHAH an S4? He is 16, what does he need with a 4.2L V8? Besides an S4 he could afford would be high mileage, and unfortunately Audi's are notorious for astronomically high maintenance costs. If you buy an Audi without a warranty I feel sorry for you.
Now don't get me wrong, my next car is hopefully going to be a 2010 or 2011 (turbo V6 FTW) Audi S5, but it will be with a warranty. I love Audis....just not ones with a lot of miles.