Your refrig on propane and the CO alarm and radio will drain 24 amps out of that 75 amp battery in 24 hours. You should never go below 50% SOC on your battery So you will need to recharge the battery first thing in the morning, for an hour and in the evening, for an hour, Saturday night. Get yourself a real 14.8V capable manual battery charger that is 30 amp capable if you only want to run the gen for an hour.
Run it again for a half hour before attaching to hitch. Also while running your jack at the tongue. Once jack tongue is on the hitch, shut off the generator and disconnect the 30 amp charger. Take 2 walks around your trailer, look at roof, antenna, everything inside and outside, that things are in place, can't move while driving, and that all lights and fans and heaters, propane, etc, are shut off. Battery needs to stay connected while driving to run the electric brakes on the trailer.