Unless weather were below freezing in the daytime, moving into the RV seems better to me.
Most gensets (unless a $$$$ motorhome) are going to have a duty cycle and installation isn’t quite meant for running days or weeks on end.
A Generac with extra propane tankage sounds better.
With an attached garage and appliances chosen as NEEDS for the smallest area — the RV just outside — I could see getting by.
I just wouldn’t care to try to run a house-sized kitchen and keep it heated or cooled versus using the RV and the attached garage as transition.
I’d be looking at a man-door to the garage, not just panel upgrades, and a sealed floor that could stand up to heavy family use + pets without adding to the burden. Garage can be subdivided many ways (insulation) to “fit” needs.
Spent some years on the Gulf Coast where hurricanes are an expectation. There aren’t any cheering good stories from those dumb enough to ride out no worse than loss of power. The size and duty-rating of a Genset (and fuel) to go for weeks is not, IMO, what is provided in an RV. Chasing fuel was 150-miles from coast and a full day of being gone.
You’ve “lost” the house. Don’t lose the RV also. Minimize demand.
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