My recommendation.

For little money, get polabs pokeys ethernet, and machx.

For trivial money, get screws that are tight with small rise.
You can easily get 0.01 mm or better repeatability for not much money, around 300€.

My own 120k€+ machines run machx, and I was 2011-2012 the country sales manager for Haas, and sold 6M€+ of cnc hw to industrial customers.
Pokeys is the best cheap option.
Cslabs -IP-S is the best there is, I use it on my lathe, but it´s quite expensive. 2000€ all-in.