i was wondering, since i am about to change my color to white, i dont want the paint place to skimp out on the body work, so i want to sand down to primer myself. if i also put white primer over the ori. primer, do you think the white primer can be compatible with the paint that the paint place uses (Frost White). i know thrs an oil base and water base and they cant be combined or something...

but i already took off the moldings, primered the front bumper, shaved embelms and im deciding on sanding the whole car down to primer, removing license plates (so they can spray under there). Anything else i should do for preparation work?