I could easily get $650/month for these units as is, and could almost certainly get $750/month if I put in some new carpet and painted.

Is it possibe for me to take them down, spray paint them back white, and put them up again?

So, I suspect you didn't paint the whole picture, like getting paid to do it!

Their children did draw on the walls, but who cares, its just paint.

Plus, the fire department found that several windows in our house are painted shut and one of our smoke detectors has a dead battery.This post and its title is a reminder to all of the landlords on BiggerPockets, especially third-party property managers, that we are responsible for owners' property and tenants' lives.  

Expenses up to $2,500 are deductible in the current year unless they are part of a larger component such as a basement remodel.We would depreciate flooring separate(if under 2,500 we would deduct it in the current year).But lets say you finish a basement involving framing, drywall, paint, flooring, drop ceiling, etc.Flooring would be handled as listed above.

This unit in particular isn't in the best shape: 10 year old carpets and paint, roaches, incredibly messy tenants (they are now gone), etc. 

I furnished the paint.  

Long story but she painted my house badly and put up her own lights then rewired everything backwards.

Maybe a little low - however since we are building and I know the quality of materials we are using I have a good handle on how long they will last/cost to replace etc.If they are new builds I think most of what you would put there depends on the quality of materials used, quality of construction and the types of things that will start to wear out first based on your weather etc.Roofing, siding/windows, water heaters, appliances, exterior paint, etc are what I would foresee needing attention and the largest expenditures as time moves on (and for those of us in hail prone areas  - the random damaging hail storm)If I follow the new construction route for an extended period of time I'd plan on selling around the 10-15 year mark so I avoid the maintenance issues that will likely start popping up around then.We will use SmartSiding which has a 50 yr warranty, Smart trim and if my partner can get a hookup on some discount or odd lot Class IV impact resistant shingles we'll be using those on the roof.