Your A/C and 2 fridge's are roughly 3400W when all three are running. Less if the fridge's are newer. The A/C will demand close to 4500W at start up but if you turn it on first and leave it running (set Tstat to it's lowest setting) you are better off. Everything else?
Keep in mind:
The fridge's are off more than on
A little power management will go a long way
Extension cords will eat into your power allotment from voltage drop so use separate 10AWG cords for each fridge
You can get by with a 4500W open frame such as a Champ or B&S if you stay away from hair driers, toasters, microwave and electric coffee pots. Unplug the fridge's if you need to use any of these.
I have powered my house (fridge, a few lights, TV, gas furnace, 220V water well) with a Champion 3500.