I'm a programmer, and I'm interested in solving my own problem by building this application, but I would like to see what you all have to add, and if you would want to use such a product. 

Like dust the top of doors and the top of the thermostat.

I have just always wanted to have the tenant have some ownership in what they use, as all too many times I see the thermostat set at 80F in the winter, with the open window used to moderate temperature!!

Arrival times is another one, but using a programmable front door lock and good house manual can fix that.Do you do airbnb currently?  

Keep in mind that not all mold is actually toxic and/or dangerous.I had tenants worried about "mold" that oddly appeared around a thermostat and the outlet below. 

[off topic background]As a programmer, we sometime 'optimize' systems by the on-demand requirements.that means, do nothing UNTIL it is required[returning to the topic]In REI, where vacancies are low and long intervals between, we can 'cheat' ourselves by fixed allocations for these items, year on year and could have easily banked these values.Yes, funds will have accrued to cover 99% of the issues, but a fixed Reserves account will easily cover current needs.EVERY investor needs to evaluate the question and develop an approach to the move-out problem.

All too many of the other programmers I know spend most everything they make / live in debt.Break out of that rut, @Eric Gluck!

I have a programmer friend who created a script for me to extract 55,000+ properties my spreadsheet....

She is a computer programmer who's boss has been great by allowing her to help me and only has to go to the office for a half of a day and spend the other half of a day at home and pays her as a full time worker.Wether you select a short term or a long term investment I wish you good luck!  

The heater will produce the same amount of heat, whether there's an extra vent in the hallway or not, because it will react to the temperature in the room where the thermostat is and that would not be changed by that extra vent.