I had 11 of these and good systems in place but still had 1-2 evictions a year and 3-4 big things that were normal annoyances like plumbing leaks, damages from hurricanes, or some vandalism.

I go in, change the air filters, replace smoke alarm batteries occasionally, I check for leaks under every sink. 

At that meeting, you are gathering information...closely inspecting all areas, looking for signs of any leaks, termites, rot, and of course wear and tear as well as housekeeping in general.

I never want to return to fix a leak.   

Then when someone does try it, you have leaks everywhere!

I found a parcel approx. 400 feet away that had a petroleum leak in the late 1990's.

A good professional cleaning by a crew of apartment turn maids, some new cheap walmart slat blinds, and a pro applied coat of Agreeable Grey paint on all walls (or put it on yourself) with white trim and you might not get market rate rent, but maybe close.Stains on the walls--try one of the specialized Kilz primers.It may need some curb appeal to draw a better group of applicants than crackheads too.Stained carpet--some  carpets can be dyed or just left in place with lower rent.It won't be perfect, but save the rent money for future improvements.As long as the roof doesn't leak and it doesn't have stablok breakers or similar life hazards, you MIGHT be able to draw a decent renter looking to save some money.Just my 2 cents. 

Leaks, well, many a handy-person can fix those.  

We didn't renew their lease.My suggestion is to identify the source, figure out which room in their unit is leaking smoke into the commercial space and ask them to quit smoking in that room.

Have you ruled out seepage from a slow leak from a water heater, or pinhole leak?