Carpet and trim-out doesn't seem like a huge deal, not sure about the basement flooding.   

He painted half of the cheap imitation wood trim when he was painting the walls.

Material quality sometimes improves (i.e. drywall vs. lath and plaster) or sometimes gets worse (i.e. particle board vs. solid oak trim). 

Replaced gutter system, fixed up the yard including trimming trees back away from the house, updated plumbing.

Then you can start doing finish items like cabinets, flooring, hanging doors, trim, then paint trim, and touch up items.

.$1500 fixtures$1500 electrical$1500 plumbing$300 window$1200 paint$500 - HVAC (window units) or $3500 HVAC (go all electric here)$500 - Exterior maintenanceNot sure about sheetrock, cabinets, counters, floors, trim, doors, hardware.You have a large oak tree looming over the house.  

Trim out some bad trees and spruce up the landscaping.

I pay $80 a month for mow and trimming twice a month.

If some bushes/trees need trimming, just do it.

The duplex doesn't need a lot of capital repairs, and we have receipts for all kinds of improvements the sellers made going back to 2010 (new roof in 2016, remodeled vacant unit as of last month (new carpet, paint, trim paint), painted a few years ago, weatherization project a few years ago, new sewer in 2002, new double paned windows in most rooms).