I have a lot of experience in repaints,and I have a chance to
Bid new construction/homes. The question is price to charge
Per square footage on bare drywall and would a primer coat
Be same price as finish coat

What is the square footage you are painting?

Keeping the same color or changing colors? If you're changing colors you need to put down 2 coats.

This page has some information in terms of pricing and calculating the cost of painting your home.