You can get the Onan 4K for $2800 delivered. The hondas will about $2000 (the pair) plus roughly $40 cable. One of these should be the 2000i companion model. You can get an off brand 4K generator for considerably less than even one Honda. There are obviously advantages to each method; whether it is price, flexibility, or convenience you are after. The Onan is made for continuous duty, where the off brands are not. So, it also depends on how long you expect to run it. A portable genny can be used all around the home or farm, where the Onan is primarily for the camper, as you mentioned. However, the reason I didn't opt for the Onan is the extreme noise and vibration it produces in the bedroom area that it is adjacent to. You might not have that problem with your's.
CG 50 Amp service is two (2) 120 volt circuits with 50 amp breakers on each (x2). The other option is 30 amp service (x1). In both cases your unit is only using 120 volts; never 240v.
When 30 Amp is all you can get, you can adapt your 50 amp cord to 30 amp, but as you can see you will have less than 1/3 the current capacity as you would from the 50 amp. The Onan 4K will give you slightly over 30 amp, which would let you run one AC unit at a time. Same for the pair of Hondas. It is possible to run your unit on these, but will require careful, manual, power management. A 50 amp generator is also available. I would think these are in the range of 5500 watt units or higher. That would be a single large Honda, not a pair of them. These large genny's get very heavy, needless to say.
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