Is there a gardening or buy-nothing group in your area? They usually have people willing to trade or give away things, especially clippings for propagation.

I’ve amassed a fair collection of nursery pots, plus a bunch of random nice ones, and for some reason since local planters are absurdly expensive ($16-$18 for a plain 10” clay pot with no saucer at the local hardware stores, ridiculous!) I buy them in packs online. Haven’t had any broken in shipping yet.

I save and replant tomato seeds each year. Apparently there’s some bacterial problem with doing that, but it hasn’t affected my plants that I’ve noticed.

My local library has a seed library, it’s free. My experience with this is mixed as some of the plants germanated were not what the seeds were labeled. I also get seeds from Gurneys online and have had success there.

Pots and planters i get from big box stores, as these tend to be cheaper here.

Actual plants I get from local nurseries, we have several within 30 minutes drive.

I grow mostly food, and I plant root ends of green onions, sprouting garlic, and sprouting potatoes with a lot of success. Careful with the potatoes, as the grocery store potatoes may have blight whereas seed potatoes from the nursery should not.