First. FORGET THE F-150, Do not even CONSIDER a F-150.. 250 depends on the trailer, 350 should handle most of what is out there. But DO NOT EVEN CONSIDER a 150 (Same for other makes IE do not consider Chevy 10-, 20 or 30 yes but not a 10).
Trailers do not mind sitting for extended periods. Worse case (so long as you maintain interior and exterior) you need to re-pack bearings (easy and not all that expensive) check brakes and possibly renew (likewise) Check wiring (Easy DIY project) and change tires.. (8 year rule applies moving or not, more so not)
Motor vehicles sitting for years on end tend to need a major overhaul when returned to service. Though I do admit mine sat for over 3 years.. but.. the reason it sat for 3 years was a blown engine so it was a TRAILER when parked.
The last consideration
Class A with towed. 8 MPG campsite to campsite 25-40 MPG campsite to grocery store/church/attraction
Class C with Towed MPG C-C I do not know. see above for C-store et-al
Trailer with big honking pickup 8 MPG C-C 16 C-rest..
Why I tow a car (25MPG kind Paid 2,000 for it in 2013, twice it is a 2001 Neon holds 12.5 gallons of motion lotion (Gas).
why 2000 twice 2000 for car 2000 for lub pump, base plate and the like to make it towable.
