It will be a roller coaster slide again.  

Very little cosmetic work needs to be done, the kitchens are updated, the floors are done, there is even new wiring, plumbing, roof, and windows. 

I learned NEVER EVER to let the guy paint (honestly; I've been able to paint a room, the windows, the baseboards AND French doors while he's still working on one window).You mention you've been able to purchase your units with cash. 

Others won't provide a CO with broken windows, interior wall damage, etc.

Some of the more bizarre: A window for an old Jeep Cherokee was left behind (found behind a door).A new, crated shower stall was once left in my parking lot (there was some weird story behind it like the tenant had intended to use for an in-laws remodel).Too many artificial x-mas trees to count.A machete (under a mattress)On a turnover, I once vacuumed under a refrigerator of a condo and just kept sucking up dried up dead small birds the tenant's cat had hunted and left behind.

For example, you might have a requirement that "ALL windows and screens are complete and functional, with no cracks or tears".

This means board up any broken windows and doors.

The older one has window a/c units.

In 2014 I completed renovated the basement suite from flooring to ceiling, kitchen, furnace, bathroom, windows etc.

I just had an operation and one of the nurses, who is married to a Tampa Policeman, said he bought a SFH on the wrong side of town and they did some fixups with all new windows to sell the place.