We're realizing that unless we buy something less than 20', we can't even get it around the driveway, and there's no place at all to store anything. So we're looking at storage lots, of which there's one about two or three miles away.
The unit we're seriously considering is at a dealer, and we've found that if we buy from them, they give a discount on purchase and installation of weight distribution hitch, brake controller, sway bar, and brake actuator.
We can't buy from a private party because of the finances involved - too complicated to discuss here, but we aren't in a position to pay cash right now.