Zap I don't know how good of a buffer you are looking for or how much you want to spend. Here is one similar to the one I have. I'm an ex bodyman/painter in the collison industry before I went to work for an insurance co. Mine has many hours of use and has been trouble free. http://www.ebay.com/itm/Makita-7-Sa...andblasters&hash=item20e83b5716#ht_1288wt_662
I have one like this: http://www.harborfreight.com/6-in-variable-speed-dual-action-polisher-69924.html I've never used it on the cars, but I did so a set of 22.5" aluminum wheels and it worked nice. Haven't used on the cars cause I haven't washed them in years, never mind used wax.