For cheese NOTHING beats Sam's prices. $11 for a 5 lb bag of grated cheddar, mozzarella or jack cheese, about that for a big 5 lb block of cheese, but the blocks may only come in cheddar. We were going to mostly have to give up cheese because it is so expensive but when I found out how cheap it is at Sams we actually buy more. I also buy tortilla chips there - a six pound box for about $7-$8 sure beats even the store brand 12 oz for $1.59.
If you want something cheaper for periods, check out something called the keeper. It is a rubber cup you insert and it will hold all the fluids for hours. Periodically you go into a bathroom, empty it, rinse it out and re-use it. NOT for me, but I know women who love it because it is a one time expense and doesn't contribute to landfills. One of the top pad/tampon companies has come out with a version of this that you throw away, I saw a video about it but can't remember which company. Supposedly is it more comfortable and leaks far less and is more secure for sports but it isn't something that I would have tried. I also am thankful that I no longer have to deal with periods.
As for oxyclean, it is a hydrogen peroxide based product and I find applying peroxide straight to the stains and then using a bit of dawn dishsoap to the stain works as well or better. It is super helpful to either have your peroxide in a spray bottle or to have the safety seal intact on the bottle with a small hole poked in it so you don't get as much out at a time.