At the end of the year when you do your taxes your interest will come back into play but is calculated outside of the OE.A couple of more items to take into account are:LandscapingTrash RemovalTermite and Pest ControlFire and Safety Inspections (Fire Extinguishers and Smoke Detectors)Supplies (Office and Maintenance)Never assume a vacancy rate.

but not to look for info to improve my own biz, but just to surf through the various areas I feel well qualified to answer questions on, often from "newbies" who may need just a little pointing in the right direction or other times, unfortunately may need to be given the tough to give answer that they need to reconsider their entire plan, ideas, etc as it may very likely result in money I assume they've worked hard for, going away like a puff of smoke!

Holy smoke! 

Pants hanging off their butts, smoked and left butts laying outside.

I really liked how nice it was and I got to know the neighbors and they're really great too.Purchase price = $31,500Rehab = $6,000 (approximately)Work done:+ Painting all rooms in the house (needed primer to cover ugly colors) + ceilings and trim+ New rainfall tub/shower faucet + plumbing+ New ceramic tile tub surround and tile base around the room+ New toilet+ New glass block window in the bathroom+ New windows in the entire house (except for large picture window), double-pane vinyl windows with tinted UV protection+ Basement laundry tub plumbing repairs+ New water heater+ Drywall replacement in upper bedroom around stairwell+ New outlets and switches in all rooms+ New light fixtures in two rooms+ New kitchen floor (sheet vinyl) also used on back hall and stairs to basement+ Miscellaneous (some new cabinet handles, smoke detectors, CO2 detectors, door knobs, new locks, curtain rods, curtains, light bulbs, grass cutting and gutter cleaning)Rented out at $875/month + utilities.The tenant I have is actually one from one of my other rentals. 

It also does not prevent a landlord from prohibiting the smoking of marijuana on the premises consistent with existing smoke-free statutes and ordinances throughout Illinois.

we have an LLC in Washington State (which doesn't have any income tax--until the nuts in Seattle try once again to make people who work hard "pay their fair share" so the lazy people can smoke weed in Pike Place at lunch time during the week..seriously happened once again today!!!)

When I first discussed what we were doing with them, they were intrigued, but did not have an existing "box" into which to classify all these sensors - like they have for smoke and CO detectors, sewer back-flow valves, etc.   

No cost for equipment and it comes with a smoke detector.

I've used the Kilz Original Primer to cover the cigarette smell after a tenant moved out and it worked like a charm.