And like some body-snacher flick this parasite has taken over the "wholesaler" space all but totally, zombified creature feeding on your capital vs brains although they do consume a considerable amount of ones patience as well. 

Smells of cooking or smoking are likely to do so as well.Having said all of the above, the flats I'm familiar with have rented reasonably well at market rents.

After moving in they began to complain of a cat urine smell (which does not exist) and demanding that I replace the carpeting.  

Wired internet cables for laptopsObviously towels, toilet paper, shampoo, body wash, etc in every bath Keurig for coffee if they'd like someGym in basement Washer/dryerLocks on every bedroomMaybe even a fridge full of beer and water

Because as it piles up back there and does not get cleaned up it's so smell very bad quickly.

I have reasons to trust that guest and his report, and we came the next day after they checked out and didn't smell cigarette smoke.

Tenants can throw a rug and take their stains and smells with them when they move out...It looks classy and is our go to move when rehabbing a rental.

BP does not need busy bodies.

Almost no body told us about Root barrier, which are simple digging  about 2-3 into the ground, near your foundation to cut invasive  tree roots. 

Any excuse you give (you SHOULDN'T) will be met with challenge, bargaining, threats and sob stories.These people are wasting your time and driving away other customers in your business, and making trouble for you with the municipality, to boot.You're also being too soft and they can smell it on you.