I'm using a Craftsman 8.5cfm compressor with a 25 gallon tank at the moment but it's borrowed just for testing purposes . It does well with the air needed to spray lacquer but I suspect it will need a bit more to spray water coatings.
The pump itself is on a cart on wheels and it weighs 65 pounds or so. Not bad at all to carry it up the stairs or take it in and out of the van.
I thought about getting a bigger compressor and mount it in the van then run long air hose to the pump.
I quite like the 25ft hose length; perfect for spraying a kitchen or doors in a booth . If you wanna keep the pump outside though, you'll need a longer hose but 2 hoses instead of 1 like the airless make the job harder with a longer hose that's why I prefer the 25ft.
When I will spray some waterborne coatings with it, I'll make a new thread about it so people get an idea of what it can do and what size compressor is needed for this particular model.