I'll throw some popular ones out there!
- https://www.deviantart.com/pacapillars - Pacapillars!! They're a very soft and squishy species, and for FTO (first time owners) the price range is at like $35?? (the last FTO batch was that much at least.) The community is also VERY nice! The discord is fun to be around, too. You get sneak peaks of adopts sometimes.
- https://www.deviantart.com/sushidogs - SushiDogs. I have one myself, and I really love them. Starting bids for auctions tend to be $25, but they do sell for over $100 sometimes. Best bet would probably be spending $25 on a MYO once you're confident in your art and designs. (Or you can get someone else to design it?? Not very sure on the actual rules of that, though, so you should probably read up on it ^^)
- https://www.deviantart.com/bub-chi - Bub-Chi seems to be an interesting batch, and the adopts are usually in the $10-20 range. (Maybe more or less depending on who designs them and all that jazz.)
- https://www.deviantart.com/necrotoyshop - Necrobies are my next favorite thing, I promise you. They're dolls based off of stuffed animals, and they have a filling inside of them. You can make these as personal as you want, too, especially if you get an MYO. They hold a scribble gacha where it's $20 and you legit JUST need to scribble it. (They only hold it once a year, however </3) Official adopts tend to be over $50 while Guest adopts are $50 (or more??? They only really have one set of guest adopts, honestly :'))
- https://www.deviantart.com/darling-dainties - Dainties, probably one of the most popular ones I've seen on this site alone. There's minimod raffles where you have to pay $35 for the dainty if you win it, though. (There's a lot of great designs, too.) I haven't had much interaction with the community, though. I just know they're pretty dang popular.
that's all I can think of, though! I would throw in another one (PupPoppies) but I'd be biased for it since I'm a mod for the community ^^ However! If you'd like to check them out too, go ahead.
Hope this helps out a bit!