If you want to go cheap and don't mind a little louder then the champion 3400 watt inverter with remote start is the way to go. It's like $1000 to $1100 . The down side is it's got a small tank and you will need a extended gas can.Looking into ones that have remote starting now. And one i can hook up to an external gas tank but i think most are able to do that. Theres a champion i saw thats remote start but i think it may be too big.
IMHO you need at least 13.5k to 15k btu ac out here. It gets warm to hot in these vans and it takes that size of ac unit to keep the van comfortable. It's going to take that size of generator "3000 watt" to run ac and TV charge batteries ect.