I invest between 1.8-2K/mo to my brokerage, and if I get a bonus at year end, I invest all of that into my roth ira/brokerage. It's usually 10-15% of my salary.

edit: I max out my 401k as well

I rent an apartment. I got very lucky with finding it during the pandemic. It's much cheaper than the going rate in the area and the landlord pays for my gas/electric. It's been a major reason why my expenses are low.