But if you will be dry camping a lot, you should look at a few things, at minimum. You should do a practice run over a few days at a campground or your driveway - just don't plug in unless you have to. Pretend you're at deer camp and see how long your power lasts. I think you'll be surprised at how fast things run down. I just did the following updates on mine (2013 26.5 RLS):
Changed out the battery for two Costco golf cart 6 v batteries. Much more power than the Interstate you got as stock. Throw away the stock battery box, the whole compartment is vented, so you don't need it. Two 6v JUST fit.
On the dealers advice, cut out the 30 amp fuse that goes from the converter to the battery and put in an automatic 30 amp breaker. The converter (charger) can put out greater amps than normally called for with the stock battery, so can blow the fuse. With the breaker, it may blow and reset a couple of times with the high load, but will get you charged up again when attached to shore power.
I went with a 600w inverter - not near enough to power everything, but it gives me decent possibilities, although no toasters, microwaves or AC. We use it for the TV (DVD/Sound is 12v - go figure). More than you need for the air mattress. It can get to be a project if you want to fully integrate it into the electrical system. I took the easy way out. Mounted the inverter on the other side of the wall from the batteries. Then bought a heavy duty extension cord and snaked it with the other wires that pass from the baggage compartment to where the water heater is. Once you get over your fear, the interior divider between the baggage compartment and heater is real easy to take out and put back. Then up through the "floor" into the area in the cabinet where the TV outlet is. I drilled a hole big enough for the cord next to the outlet, and glued in a desk collar from Home Depot to make it look nicer and protect the cord. Now I can plug the TV into the cord when needed, or extend the remainder of the cord to other interior areas of the RV if I need 120 volts for something. The only option I missed was the remote on/off switch sold for the inverter - they all require you to turn them on or off now, so without the switch located inside the RV, you have to go outside to the baggage area to turn it on, then remember to turn it off again (and they suck power when not in use, so can run your batteries out if not turned off). That's my next mod.
Of course, you really should look at replacing all the bulbs with LED's too. I got mine from Amazon - cost about $75 to do all twenty in the living areas - they are China Cheapies - good light, but poor mfg. tolerances, so they don't all make good contact. May have to wiggle one or two to get them back on after a day of vibration on the road. Or order extras, so you can find enough dependable ones.
I haven't stress tested it all deeply, but a couple of weeks ago this worked very well for 2 full days of dry camping in the Big Horns. Std. water usage, did not obsess about light usage (even during the day) and watched 2 hrs of "Mad Men" each evening. Jayco battery gauge (the 4 idiot lights) says I only used 1/3rd of the battery power over the 2 days. So I probably could have done one more, before sinking to under 50% capacity, which is when a recharge would be needed. I would have run out of water then, anyway...
Maybe someday I'll go full solar to charge the batteries, but for now, this looks to be a good solution for short dry camping stays.
Next test will be for three nights over Labor Day....
2012 Ford F-150 Eco, Max/Max
Jayco 26.5 RLS, Reese Sidewinder