I have found that start up costs can be significant.
I started with a garden and fruit
trees. The fruit trees died and the garden needed hoses, hoes, seeds, and fertilizer. I did get good vegetables but I cannot say that I saved money: I *MIGHT* have broken even.
The next year I already had tools so I saved money by
gardening, but I bought (fewer) fruit trees and gave them better care. They lived. That second year I made money on the garden but I broke even because of the money spent on trees.
Then there were the
chickens, and the bee hives, and so forth. Canning jars and the big canning kettle paid for themselves in a year or two.
Basically, every time I spend less on food I invest the money saved into something else that is usefull.
I am having a lot of fun. I have a home made green house, a big garden, the worlds freshest foods, and so forth. However, because everything had a start up cost it took a few years to actually save money: I sank all of the savings into the next food-producing enterprise!