with you getting your rims sprayed black and tinting your windows and getting and upgraded exhaust if you have a lease of course and what do you do when you return your car so that there are no fees or anything ?
Also, if you lease from outside the dealer (e.g. not thorough Audi Financial), you can get away with it. It would have to be a bank lease (which generally gives you a much lower rate than Audi Financial). Checkout http://leasecompare.com they are awesome and you can even re-lease your car to get a lower rate.
Check with the leasing company beforehand. They'll most likely tell you that when you hand the car back (if you plan to do that) that you should return it to standard. If you leave it as it is, then its very likely that they'll charge you to return it to standard.