I'd say FD's extension cord idea is a very reasonable way to go for the reasons he stated.
That said, I've always just gone ahead and jumped in the deep end--30 amp shore, 3000 watt inverter and 3000 watt quiet inverter genny. I'd have put in solar as well but my 20' long skoolie just doesn't have enough roof real estate to make it worth while.
I chose the progressive Dynamics 9245 smart charger with the remote "fob". I've used it for several years and so far so good.
Jack