The sq ft price also doesn't matter because a 1500sq ft 3/1 and a 1000sq ft 3/1 will have roughly the same kitchen cost and the extra 500 sq ft is generally the cheapest part of the rehab with paint and flooring 

If trimmed, are you looking at solid finish Oak or basic 1x trim to paint?

Find outdated units and add great rental value with paint, new light fixtures, smart locks, etc. 1B. 

The side where he lived just needs paint and flooring.

It's unclear if this is discoloration from an old leak that bled through the ceiling paint that was applied during the April renovation or truly an active slow leak somewhere.

Quote from @Tim Delaney: @Marty Boardman thanks for sharing - just to be clear you put all your expenses related to the house under one capital improvement account t (Wip) and do not bother breaking them down into categories like kitchen and flooring and paint, etc?

My suggestion: buy a quality small MF that needs paint and carpet, even that is difficult enough if you are remote!

What is your go-to paint color and brand?

The other air quality issues are mold, lead paint and rodent feces.

Typical cosmetic (lifestyle) upgrades we do are better/more LED lighting, dimmers, flooring, paint, trim, solid wood door slabs in place of the hollow core etc.