I think rock salt would be the cheapest to use, depending on how big your freeze is. Just my take on it. I usually buy a big bag of it that is used for some water softeners and use some of it. I have never used any other kind of salt other than rock salt.

Sue

Rock salt is much cheaper. It probably won't disintegrate as fast as table salt, and may keep things cold longer. I bought an old fashioned crank ice cream maker and it is the first thing the grand kids want to do when they come here. I was hoping to see some delish recipes in this thread. Maybe some will come!
Suzi