Estimate how much paint you need to buy for your walls, taking into account doors, windows, and the number of coats.
Should I use a primer?
Yes, using a primer is highly recommended, especially when painting over a dark color with a lighter one, or on new, unpainted drywall. A primer ensures better adhesion and a more even final color, which can sometimes reduce the number of top coats needed.
What if my walls have texture?
Textured walls (like stucco or popcorn ceilings) have more surface area than flat walls. As a rule of thumb, add about 10-20% to your total paint estimate to account for the texture.