What is your build objective?
Weekend warrior/once and a while/family trips occasionally...or full blown 'expo' build?
For your gladiator:
1) A 100Ah battery lithium would be a huge luxury. 100Ah lead acid (50Ah usable) is MORE than adequate. Many are using a 68Hr Grp 34 dual battery setup in their Jeeps. Get a DC/DC for lithium. A DC/DC is a very nice to have for LA.
2) 500-1kW inverter for LA 100Ah. 1500W - 2kW (pk) for lithium.
3) tent heat : Mr Buddy Propane Heaters are the easiest. These are safe and many like them... biggest issue is freezing of the small bottles in really cold weather. Also, condensation and oxygen refresh must!!! be managed.
Diesel Heater (Happy Buy or equivalent) put combustion outside (preferred) of the tent. I have diesel heaters and will never go back.
4) Solar - 100-200W rigid solar on top...either the cab or mounted on roof of Hardshell tent. Get a Victron controller.
5) 2 adults/1 kid in typical hardshell (narrower than queen bed width - usually a double) is going to be tight ... Depending on your size, no one will sleep well. I'm 6', wife is 5'9, kid is 5 and over 4'....we don't fit/sleep well in those setups. We are not overweight, but are not slight in frame. Look for a larger clamshell RTT (like ikamper) for more comfort. Your kid (and you), if not full grown, will want the space. The iKamper hardshell will help somewhat with the wind.
6) typical soft RTT/like collapsible bags take a look time to setup/teardown. Don't underestimate the annoyance of doing this on a roof - especially in the wet/wind/super dusty situations. Wind sucks in these units...big time.
7) Guys that run an open bed gladiator and then stack it full of expo gear ...personally I think are nuts - everything/everyone gets filthy dirty/dusty. To each their own...
Running a fridge and any electronics in an open bed is asking for trouble. The are a few that I know of that have gone this route AND have used it extensively (not fair weather only types) are relatively unhappy.... I'd suggest a sealed cover/top
8) if you do the above, bed organization is going to be important...being able to put stuff in the front (never touched, but important like a battery) vs gear at the back (food/water/toys) will drive certain behavior. Drawers, platforms,.etc. Or plastic bins...
Post some ideas/goals, and folks will be able to help you.
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