Biggest need for most folks is Heirloom seeds that allow reproducing year after year. Unless you get Heirloom you will be buying 'Terminator Seeds'. These are under the control of the 6 companies that produce seeds and where you can't keep planting from the seeds you get from them as they are hybrids.

Next biggest need is a 7 quart pressure canner. Times were you could find one in EVERY complete kitchen. Today you are lucky is a yuppie millennial has a complete set of pots and pans. If you do find one at an estate or yard sale you can usually get its pressure gauge tested at your local county extension agents office either for free or a couple of dollars. They also do soil tests for folks so they can get their ground where it can grow things. Right now I am up to three pressure canners. One from the wife's Grandmother, one from my Mother, and the third I bought from an estate sale. This is probably the biggest expense folks will have.