Mrsapalm,
We rented the fridge at POR last year. Since I had 4 kids I thought I could keep some water bottles and milk and juice in there. No can do.
A quart size carton of milk maybe. As for a loaf of bread, it will have to be a small one and not much cold cuts. We returned our fridge the first night. Couldn't use it. Luckily I had packed food snacks in a collapsible cooler and we wound up using that during the trip. Worked great. Kept it in the tub filled with ice. kept a gallon of milk, juice, sodas you name it. Just refilled the ice every day.
My opinion, I would get one of those collapsible coolers and save the $10 per night. Another plus, once you've eaten all your goodies, you can use the collapsible bag as luggage to pack all your souvenirs.