I like ants. I paid 0.30€ per tube and I don’t think I’ll ever need to buy more, I use old plastic food containers, so free, I breed my ants’ feeder insects…
I mean, there are many hobbies that can be dirt cheap or free. Do you like plants? Get free cuttings asking for them to your neighbor or any acquaintance, buy a little dirt and cheap pots. Do you like fishes or crustaceans? You don’t need an expensive aquarium, you just need a really cheap food grade plastic tub. Do you like bikes? My bike is a cheap second hand one. Do you need a house? Forget it, you’ll never be able to pay for one.
You can jump up from 5 to 7, even more depending on the snacks.