What quality do you expect, looking to do just a base coat or looking to go with something special?
An "Earl Scheib Special" guestimate is 1500 to 2500. Materials you would be at 500 or so.
Doing some pearlized special paint, materials alone could be 5500 or so. High grade auto paints arent cheap...600-800 a pint isnt uncommon. A pickup is 2 gallons for point of reference.
Doing a truck, you gain a high degree of economy by scale. Painting a panel 4x bigger doesnt take 4x as long...more like 2x. Your set up/tear down is the same, your still only masking 1 time - just more of it...ect.