I am going to rent an air compressor so I can paint the car. I bought a paint sprayer for it already. Problem is I am not sure how big of a compressor to go. The sprayer says it needs a min of 40psi I think but doesn't say how big of a tank to use eg 6gal? I know it needs an oil-less. Anybody recommend any size or tried the small ones before. Will the small ones fill up quick enough to not screw up the paint?