The min. is what I have. Ugh.
I stay in the north in the summer and Florida in the late fall winter and early spring.
The min. is 10" I beam frame, 6,000lb lb axles, single pane windows. Kinda the run of the mill rigs. My rig is a 2011 and we spend 10 out of 12 months in it. Everything works. I fixed a few things, shower leaks because rig flexes going down the highway. The fridge door panel needed trimmed, I put Michelin XPS Rib tires on it, I rewired the lites, and slide main panel. All the fixes were easy looking back after I understood the real issues.
We like the interior still, and the storage is larger than more expensive units we looked at.
The air leaks in my rig keeps fresh air coming in...as the silver lining.
About 15 days in 10 months we are too cold and run fireplace and two electric heaters to stay warm. If we remove any source of heat the rigs cools down fast.
Two A/C units can keep you cool. We use it as lot while in Florida in spring.
Rigs that are a min. to me now are the Trilogy, Landmark, Presidential.
The custom rigs are overkill.