At the moderate hotels the fridge is free, and is installed inside the furniture in the room (in a wooden cabinet to match the decor). The fridge is a small cube - dorm size - but will hold quite a bit.
There is no freezer. In addition, the knobs to adjust the temperature have been removed, so sometimes the temp is either too cold or too hot. I had frozen orange juice the last time - ice crystals throughout! If the temperature isn't right, just call maintenance, and they will come with a knob and adjust it.
There is a $10 per day charge for refrigerators at the value hotels. You need to order it, and they will deliver one to your room.
So, bottom line, since you are staying at POR, you will have one in your room for free. Enjoy your trip - I love POR!