This may sound dumb but I've done this:
Sand the doors down, do any body work if needed, and prime them. If you go to bare metal you'll need to use etching primer. Once you have done all the prep work, take them to Macco or someplace like that. When you get them back, sand them with 2000 grit sandpaper. Use water when sanding, and sand very light. Then polish the doors yourself using a buffing wheel and a paint polish. Most of the work is done by you but the spray is left up to them. So just prep them, and finish them. With a little work the doors will look perfect and it wont cost a lot.