Yb,
First off, you are in Ontario, and that is as bad solar-wise as Michigan. The little panel on the roof will probably do a good job of making up for the loss when the coach is stored.
As for running the generator, you need to do this soon. Find some open place to park for a short time. Fire it up and put some load on it like the A/C. Then, go out and walk all the way around it at different distances. You may find that the noise is generally in one direction. Remember that and when you next are at a 0HU location, aim that away from everybody else.
Also, if you watch the voltage of the house bank, you can probably develop a better feeling for how often and long you need to run the generator to keep it up.
Matt