My inverter is MSW as pure sine wave back in 1997 was over $3 per rated watt, and not nearly as energy efficient as today. So a 300 watt inverter was something like $900 back then. My 1,500 watt Trace M1512 inverter was $750 'on sale'. Back then a 75 watt solar panel was also very expensive at $375. Today you can get a framed 140 watt solar panel for $229 at the link provided above.
Watch out for 'unframed' solar panels designed for mounting on homes, where the framework is installed on the roof, then panels mounted to that frame, then wired to the HOME, not a RV. Some of the frameless panels are $1 per rated watt or less. They do great at what they do, that is provide a 6 KW system for a home at the lowest possible cost and weight on the roof.
Yes you can get by without a gas oven, by installing plenty of solar power. I have a toaster in my RV and it will draw 75 amps from the 12 volt battery bank. The 15 minutes it will cook will take 3 hours of full solar production to recharge my batteries. So cooking longer than 15 minutes is not practical, unless you have well over 500 watts of solar installed. Better to just fire up the generator if you will be running a 2000 watt convection oven to broil a steak for 30 minutes. . .
Yes 4 golf cart batteries can supply 150 amps for 105 minutes (their full rating) and I have run my microwave for about 15 minutes (3-5 minutes at a time) from MSW inverter drawing 150 amps from the batteries. However it made the microwave cook so much slower that I had to replace it. Now I only run the micro on generator power.
You might consider three inverters. I rarely run the big inverter while dry camping. It is not energy efficient at running just the TV set. I have a e-meter that carefully measures the amp draw out of the batteries and counts down what leaves, and what returns. My big inverter running a Direct TV receiver, the 19" tube TV and other loads in my RV might show a -8 amp total. If I shut off the Trace and plug in a 150 watt inverter, run the TV on that, total amp draw is dropped to about 6 amps. Saving 24 watts is important to me when I want to stay parked for a week at a time.
The big pure sine wave inverter might have a larger than average standby amp draw, and say you have a 200 watt load, it might take say 240 watts input, or perhaps 275? While a 300 watt $35 MSW inverter might only have 220 watts input with a 200 watt load, due to it's much smaller capacitors, and transformers, ect.
I have the small inverter plugged into a cigarette lighter receptacle that I installed next to the TV and VCR. The factory installed #8 wire to the TV antenna and near the VCR. It is fused at only 20 amps, but that fuse has never blown in 20 years!
I have recommended people install a couple of cigarette lighter receptacles in their RV's with #10 wire and 20 amp fuse, using copper wire for supply and return to reduce voltage drop. I have run a dirt devil from the 150 watt inverter to clean up the old class C, and it worked fine. With the new class A, I would run the inverter/charger or 4 KW generator to run a larger home sized vacuum. It draws around 500 watts. . .
There are not that many loads that require PSW. Microwaves should be included in them. So would a compressor motor, that requires high torque. Charging cell phones, laptops, and ink jet printers run fine on MSW. Laser printers require PSW.
GOod luck with your system and have fun dry camping!
FreeCampgrounds.com offers some great dry camping areas, many are free.
Fred.
PS: Yes L-16 batteries have been used in many home applications with 100+ amps draw from each battery. But I don't think they are as energy dense as the T-105 or T-125 battery. That is you get say 440 amp hours from a T-105 battery pack at say 275 pounds, while only about 350 AH from a similar weight L-16 battery bank.
Personally I would avoid them at all costs due to their extreme weight. . . .
You might want to look into the T-125 battery if you can find them for a good price locally. But also know that some say to avoid them due to the less water under the plates. Some state that you have about 1/2" under the t-105 battery plates for junk to accumulate before it will short out a cell. With more plate and less space under it, there is less room for the T-125 plate to accumulate junk before the cell is shorted out.
Also some say that battery life of a L16 is less in home applications where the battery is not moved around. In a car, or RV, the battery is shaken on every move, agitating the plates, and fluffing off some 'stuff' that is not good for the plates, thus extending the battery life.
Anyway my next set of batteries will be Trojan T-105 due to the 13 year battery life that I got from the first set in my motorhome.
