As an alternative to a two stage furnace, I wonder about a vented Platinum Cat system. The fan it uses is a lot smaller and takes less energy than the fans forcing air through the RV furnace's heat exchanger.
If I had to reduce my must-haves from my relatively long list to a few, it would be a fiberglass or metal roof, Azdel sides, E-450/V10 chassis, and an onboard genset.
One thing I'm curious about... are heat pumps that better than a conventional A/C unit with a heat strip? Below 40 degrees, heat pumps stop working, but a heat strip may not be as effective as a Vornado space heater (or similar), but would definitely help supplement the furnace.
I saw the crowdsourced fundraiser for that. Interesting ideas, and has a novel concept or two, such as the built in blender, but I wonder how long the battery would last on that, just as stated above.
I like the idea, but I don't see myself buying it, because I either need a cooler to take stuff to or from my TT's refrigerator, or as a place to stick drinks near my rig, and I don't want to spend more than I have to for that, unless it is a cooler with good insulation that can last a long time.
Rephrasing, to make sure I got this:
You have a 50 amp connector. On one leg, you will have the 30 amp shore power. On the other leg, you want to run a Honda generator? Or, do you want both the 30 amp power and the Honda generator on the same legs.
I don't know if this can be done safely, because either the Honda would get yanked into phase with shore power, the generator gets killed by the backfeed, or you get 240 volts where 120 is expected.
I'd check Amazon reviews. I've used one product (Ospho?) that was a decent primer, and used phosphoric acid to turn rust into a more stable compound. Then added a paint on top of that. All this after a good brushing, cleaning and letting the surface air-dry for a while.
A long list of mine that are essential (to me, that is), and are deal breakers if not present:
1: E-450 chassis, V-10 engine.
2: Rear view camera.
3: Auto-level jacks.
4: Azdel or aluminum sides.
5: Fiberglass or one piece metal roof, both crowned and folded around the top by a few inches.
6: The chassis having a remote for the door locks, and the keypad.
7: A 300 watt inverter, PSW. This would allow me to charge low-energy stuff like cellphones and tablets overnight.
8: A water heater bypass for winterizing.
9: Solar pre-wired.
10: A 5000 pound tow hitch.
11: Multi-stage converter, so I can keep the rig plugged in when at home.
12: An inbuilt generator that uses the fuel tank on the chassis.
13: An EMS, so low voltage won't burn out the A/C compressor, or plugging into 240 will give a display error code, and not a fried rig.
14: Fantastic Fan, 12 volt, with thermostat, ability to run forward/reverse, and rain sensor.
15: Tank heating pads and pipes wrapped with heating tape.
Not essential, but nice to have:
1: An electric awning.
2: Quigley 4x4 conversion.
3: Macerator pump with emergy outlet and gray water dump. I saw one used motorhome that actually had both a macerator pump and a regular gravity dump for emergencies. That way, you always have a way to empty the tanks out.
4: Full solar system, MPPT charger, with panels on top.
5: 300 amp-hours of battery life.
6: A full-time, "hybrid" PSW inverter. This way, no matter what the power is on the charging side, all appliances either get 120VAC or 0 VAC.
7: An audio head with Bluetooth hands free calling and playing music for when driving.
8: Full size spare tire.
9: Roof ladder.
10: Generator management system, so if the batteries get low, the genset fires up... assuming no quiet hours set.
11: A Cheap Heat system so if on hookups, no propane would be needed.
12: A water heater with both electric and propane.
13: A convection microwave/oven.
14: An accumulator tank so the water pump is quieter.
15: Mounts on the roof for RotoPax gasoline containers.
Pie in the sky wants:
1: A rear hitch that can tow more than 5000 pounds.
2: A 5500 watt generator, and 50 amp service (in reality, one leg for one A/C, the other for the second A/C and everything else.)
3: 1200 ampere-hours in the battery bank, so a residential fridge can be used when boondocking.
4: A hydronic system with a radiator in each storage compartment and near the tanks.
5: A Platinum Cat system, so I can minimize the use of the normal furnace when boondocking.
6: Fold-out solar panels on the sides.
7: A flexible solar panel on the awning as well.
8: A propane fuel cell like the Truma VeGA model. That would mean no worry about keeping batteries topped off, and would mean an efficient compressor refrigerator can be used while boondocking.
9: A clean-out, watertight hatch to all three tanks, 8-12 inches in diameter. This way, if there is a poop pyramid, it can be dealt with by a plastic scraper and a wet/dry vac, and clogs are easy to deal with.
A bedroom A/C can be noisy as well. Even my ducted A/C is loud enough to be distracting at times. Some of the portable A/Cs that vent out a window are surprisingly quiet.
I wish someone can make a portable A/C with one duct going to the outside, another duct going elsewhere. That way, the bedroom door can be closed, deadening the noise from the A/C, while it keeps the area cool.
I have been thinking of a fuel petcock on the gas line. That way, when the generator isn't needed, I can turn the gas off, fog the engine, empty the lines and carb, and the generator should be worry free, other than winding corrosion, which running monthly helps take care of.
I wonder about bigger wheels and/or flipping the axles. It might require a decent welder, but it would add a couple inches, which can be the difference between carving ruts in the ground and not. Not cheap, but cheaper than a new quad trailer.
Some "C"s can go off-road with a Quigley conversion (if on an E-350/E-450 chassis), or directly (if on a F-450/F-550 chassis.) For a lot of people, this doesn't mean that much since "off-road" may mean a gravel pad, but being able to go off the beaten track a ways is always nice, and higher ground clearance can be beneficial.
After a certain unnamed lube joint caused $2000 in transmission damage to my old truck by slicing open an ATF hose, there is no way I'd ever trust my vehicle to those shops. I much prefer a good independent shop, a decent dealer, or in a pinch, me with an oil evacuation pump (I use one of these because it sucks up the sludge that builds up in the oil pan, and newer European cars don't even have a drain valve anymore.)
Sprinters have been well discussed. I would highly recommend either you doing the "A" and "B" servicing yourself (and it consists of more than just an oil change, especially the "B" one), or having a good dealer or shop which can handle Mercedes vehicles do it.
With four people, I'd go for a rig no smaller than 30 feet, and some cars can be adapted with a lubricant pump for towing on all four wheels.
I have seen some very well laid out "C" floor plans with multiple sleeping surfaces so everyone in a four member family gets a bed if they so chose. One plan even had a seat and a place to play console video games inside, when weather was not friendly to being outside.
I would highly suggest slides. Yes, they have drawbacks, but the space they give can mean a very pleasant trip without the feeling of being cramped.
I have a propane wand and glycerin spray (I don't use soapy water due to it corroding if not completely rinsed off) which I used to check for leaks or loose connections. I call it the Zippo test, and it ensures that other people keep their distance while I am checking the lines.
Here in Austin, I've gotten a lot of excuses with lazy store employees who didn't want to exchange a 20# bottle. A few of them:
"No DOT certified professional is on duty."
"Do you have a Federal license to possess a propane tank?"
"No employee is permitted to open the propane area. Only AmeriGas/Blue Rhino employees have the cage keys."
"Propane work requires two employees at all times due to the danger involved."
Of course, when I get a lame excuse, I just go a block or two and find someone else at a store who isn't playing games on their iPhone and actually is doing their job.
It may be buried, but the relay and fuse have been discussed on here and some F-150 forums. I've found Google's search using the "site:rv.net" works pretty well to find things.
From a quick search, the relay goes into position #9, fuse goes into position #21, and this is for a 2010 Ford F-150, so it can be different on yours.
There are a number of custom "C" builders out there. Lazy Daze has a great reputation, similar with Phoenix Cruiser and Nexus RV. There is a price difference, but surprisingly, for what one nearby Winnebago place was charging for a Trend (they were asking more than Winnebago's MSRP initially), I could buy a fully loaded Phoenix Cruiser which would be the same length and about the same width... but upfitted with Quigley's 4x4 option, and having a slide-out.
There are several good dealers in my neck of the woods, but since they don't sell "C"s, I probably am going to buy something from PC or Nexus RV, and if it needs any major repairs, it goes to those guys.
What is interesting is that Sunseekers and Foresters have a "hybrid" plan as an offering that has the entertainment center, but yet can also offer a bed up in the cabover.
If you can afford it, I'd go with the V-10, just because a 460 is going to be pretty old. The V-10s have had virtually all the kinks worked out, the transmission is decently reliable, can tow/haul without issue, and isn't great MPG-wise, but not horrific.