E46 M3 have a couple of issues. Early model years had issues with the vanos unit failing. SMG trannys were also iffy. Rear sub-frame issues (no issues with the vert) Those are the major problems, but there are couple of other minor things.
The only issue with the vert is that is creaks a lot.
Here is a M3 vert for sale over at MunichEvo. The owner Matt sells good quality cars. Should give him a call to see if he is able to find you a car that you're looking for..