If you're talking a 3 year old unit, owned by couple with no children or pets that took it out twice a year for vacations, about a hundred miles away, thats one thing but if it's a 7 year old unit that was lived in 9 months a year by a family of 5 with three dogs, two cats and a macaw, that's another. Most people don't want to spend every weekend working on a new-to-them trailer, having to replace expensive appliances before pulling out for the first trip.
Base that against a new-good brand of trailer that you hook up to and go, the first week of ownership, realizing that small things will break, screws tightened etc. and being fairly handy, they do their own repairs and enjoy it.