how much paint do I need?

[bibijawa]

I've decided to paint my 1989 20 sf. I want to paint the inside awlgrip cloud white and nonskid ice blue. I also want to paint the outside ice blue with a cloud white bottom. How many gallons or quarts do I need? I know I need topside ice blue and cloud white paint, h3002 converter, primer, primer converter and t0031 reducer. I am going ro roll and tip. How much do I need to buy of each? Also is 2-3 coats the standard?