I ran some extension cords a couple hundred feet and I was surprised at how well it worked. I think one was 10 or 12g, but the others were just regular, probably 16g. Ran a fridge, freezer, exhaust fan for gas water heater, gas furnace, lights, no problems.
Big thing to help, manage the loads and monitor the voltage, if you can. Fridges and freezers in the last decade or two only pull about 100W when running. Starting could be several times that for seconds, going down over a couple minutes. You can also run one for two hours, then another, etc. Just use common sense.