If you are heading to an RV park for the winter down south you will be paying for metered electric usage and it may be much higher than you may think it will be. Ask what the KWH rate is. So you may want to think of not using a electric heater but looking into getting a blue flame propane heater or a Propane Radiant heater which are very efficient. Much more than electric or you RV forced air unit.
Amazon blue flame unitAmazon Radiant heatersYou will also find vendors in many in flea markets selling these.
Like Grandmas in Quartzsite next to RV Pit Stop. I have nothing to do with this vendor. Just that I bought one from him.