In my case.. I bought a towed, 2,000 for car, 2,000 to make it a towed, that's 4,000 dollars, 26MPG v/s 8 for the motor home if I'm lucky means every time I drive to chruch (34 miles round trip or about 2 gallons in the car (with side trips) v/s at least 5 in the motor home) I save nearly 10 bucks.. that is about 1000 a year in savings in gasoline alone assuming I make choir practice and the special services or more. not bad.
Plus it saves me packing up 2x a week to go to church.. Easier to park, and so on and so forth.
WAX is good, Wax gets me about a MPG or two, on my 800 mile migration hikes, that's 10 gallons (30-40 dollars) for a 10 buck bottle of wax.