my main concern is the heat... i found out the hard way that running the heat drains the battery quickly. i wanted to run the generator to keep the heat on thru the night
Running a genset all night to supply heat is not a good idea, IMO. I've mentioned in several threads the idea of an electric pad (not a blanket). The outside temps lately in the Sacramento area have been in the mid 40's - and I haven't had need to use the furnace at all. I turn the pad on for about 20 minutes initially - then cut it back once I am in bed. It seems to use about 4-6amps when the thermostat turns it on. So I use no propane and no DC to run the furnace. If the temps are below freezing, my RV is not there to begin with.
I have a 5000 Onan built in genset that will power "everything" at one time including 2 A/C. However, it burns about .6gal per hour. In CA, that's now around $250/hr. I also have a i2000EU Honda that runs for about 6 or 7 hours on a little over a gallon (the tank size).
So when boondocking, I use the Honda, and don't boondock if I need the A/C. The Honda will run my computers and 40A 3 stage charger. However, when I run the Microwave, I must turn off the charger or it will choke. And even almost by itself, it is obviously pushing the limit of the Honda if anything else is turned on.
Yes, Yamaha's are nice too - and they have a gas gauge that the Honda is lacking. And, yes, they are both hot items in the community of thieves needing extra dollars. The good news is the reason they are a hot item is that the resale "is" high as others have mentioned. A security chain or cable is a joke to the thieves. They come with heavy duty cutters that go through those like hot butter. I have 2 5/8" inch cables that I use - plus have covered the handle with an anti thief deal to keep them from simply cutting through to remove the cable. Another advantage of the Yamaha is that is blue vs. a bright red that is easily spotted.
Earlier this spring a fellow parked beside another RV a bit down from me - that had a 2000 with a 1/2" cable. The cable also ran through their 5 gallon gas can as well. The nex AM he got up bright and early, walked around his RV with his cable cutters, cut the cable, placed the 2000 -- and the 5 gallons of gas in a compartment in his rig and split. No one was up early enough to get a license number.
As others have mentioned, if you really examine your essential needs, you could probably get by with a Honda 1000 genset. What I see a lot of in the boondocking world now are the 1000's just running most all day vs. building a large battery bank and adequate charger to keep them up as well as an inverter. A gallon of gas will keep that puppy running just short of forever - almost. And they are super quiet. If like me, if I can't have a microwave I would most likely starve - so, as Gary mentions, if I had to I would just buy a smaller one that the 1000 would run.