There's good = $$$$
There's good and fast =$$$$$$
You might find good and cheap
But good, fast and cheap? Probably not.
Having said that, I've heard good things about Mr John's bodyshop in Vaughn. European Autobody is good (owned by the Remo Ferri Group) but will not be cheap.
2009 E92 M3 Le Mans Blau on Schwartz. DCT, EDC, TECH PKG, M Drive. RAC RG63 19x9f ET22 19x10r ET22, Yokohama Advan Neova AD08 265 30R19f 295 30R19r, Ground Control Coilover Conversion, Eisenmann Race Exhaust.