After reading Jessica Mitford's 1963 muckraking classic "The American Way of Death", my eyes were opened to the outrageous scamming of the bereaved that has long been perpetrated by the funeral industry. Ever since tthen, I have always said that I didn't care what happens to my body when I die so long as nobody spends any money on my funeral! The laws can vary somewhat by state, so it is a good idea to check for your area, but in general the following tips hold true across the US.
Embalming is not a legal requirement, and unless you need to ship the body or postpone the burial, it's not necessary either. Your body is going to decompose one way or another. This is true whether or not you have a sealed, "air-tight" casket or not. So you can skip the fancy, sealed caskets, and especially the metal ones. If you do need a nice casket for a viewing, why not just rent one and skip the wasted money and resources?
There are lots of inexpensive options that you may not be told about. For instance, all that is needed for cremated remains is a cardboard box, though they will try to sell you a vastly overpriced urn. In many places, home burials are legal. If you choose to go this route, you can may not have to hand over the body to the funeral home at all, avoiding the predatory charges involved. Remember to check up on the laws of your state, as many funeral directors have been known to straight-up lie about legal requirements.