The good chair manufacturers are well known. Herman Miller, Steelcase, Humanscale. You wont get a good office chair for less than $500.
Mesh is common in higher end chairs. Lots of adjustability, moveable lumber support, adjustable armrests, adjustable height/angles, leg support, conformability.
Keep in mind, if you invest a lot of money in a chair, that chair will last for 10+ years and still be good. If you don’t have the money now, buy a chair from ikea like the Ikea Milberget for like $65 and save for a 500-1000$ chair. That’s my plan.
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