Low 20s Art for one that is in minty shape, as mine is (48K miles but extremely well maintained).
Manolito is correct that there are some ZHPs out there right now on autotrader, cars.com etc. some in the 75K mile range are priced in $15K and below and are fantastic, reliable cars and great daily drivers. IMO this is one of the best bargins in used car right now because you get 3 series reliability but with M styling and tweaked performance...in a very affordable package. Coupes tend to be priced 4-5K$ cheaper than cabs.
What brand new convertibiles are out there now in the low $20s that can compete with this :
