Welcome to the Truck Conversion forum! Wow, that's some low miles on that truck. Sounds like it should make a good base. I live in MN so my truck is parked half the year. But we do try to get it out as soon as warm enough and keep driving it when it's pretty cold out. I only have single pane windows. I kind of wish mine had double, as well as more/better wall/ceiling/floor insulation. I think that would help us use less propane to heat it on either end of the camping season. I bet it would be quieter inside too.
'03 Freightliner FL112, 295" wheel base, with '03 United Specialties 26' living quarters, single screw, Cat C12 430 h/p 1650 torque, Eaton 10speed , 3.42 rear axle ratio