how much should I spend to get a better turntable than my current turntable?


You want details hah!
I bet....

CURRENT: mmf-2.2. A lemon, a complete junk in my opinion. A disaster from the start. What I can I do with it? It was delivered with missing screws, the lift arm level broke in 3 months, all I got in the name of warranty a list of things not under warranty. I don't want to criticize the brand, maybe I just got unlucky, they are otherwise great. 

What should I get for the littlest investment that would work better than this wobbly, squeaky  thing? 

grislybutter

I would not invest in a TT less than a couple grand (as a recommendation). But what is the rest of your system? There is a place to put photos and your components under your user ID. This is very helpful for us to help. The best TT is highly dependent on the associated equipment. Mine is about $20K… without the Phonostage. Before this, in the previous iteration of my system it was about $8K.

The sound is your TT + cartridge + Phonostage.

The sweetspot to me has been very roughly the cost of TT, Phonostage, Streamer, DAC, preamp, and amp roughly the same.

Just go and get a new Rega P2. Simple and well made. Nothing to go wrong.

The cheaper Project are junk in my experience.

I bought a new Pioneer PLX1000 to add to my collection of vintage TT’s. For $699 it is competitive with the several times- as-expensive Technics TT’s. I put a Denon 103R ($340) on it. Check out Herb Reichert’s review from several years back in Stereophile.