The US is too big for a single answer, but here in Florida bananas are cheap, but potatoes and apples are expensive. Sweet potatoes are often cheap though.
I grow some stuff here, that's not free but is cheap for sure. Okra, jalapeno peppers, watermelon, purple sweet potatoes, basil in the summer. Greens, lettuces, broccoli, cauliflower, radishes, fennel, cilantro in the winter. Mint all year. Have citrus trees and a fig, all dwarf trees so not a huge harvest but an easy one.
I think wine and most booze will get very expensive, grains, so flour, pasta, bagels. Good cheese. A lot of produce since it comes from Mexico and South America and our supreme leader here seems determined to piss them off. Milk will probably stay around the same, maybe domestic cheese. I would logically have said eggs, but apparently not.