Some folks like to do that but with a good insurane policy I never saw the benefit.

Tenants want to stay for three years so vacancy is near zero up through end of year 3.    

It's all about your tolerance for risk.

I can make an immediate COC return, and cash flow the property over those 15-years, and have ZERO property maintenance.

Second, my homeowners policy which I carry $1M liability on each property.

So you are saying that if this is my primary residence (which indeed it is and I could see myself living there for the next 10-20 years if not longer), it is probably best not to report remodeling costs ($50K) on my tax returns (as its effect on the overall adjusted cost basis of the property will depreciate to zero over 10-20 years) -- and that if I did, it would just be a hassle as it could open me up for an audit by the IRS?

There's really no greater risk of a fire with a normal indoor smoker vs the one with the tenant on oxygen in it.Now if you want to go with a no smoking policy then do it, but I wouldn't justify it (to yourself let alone them) that you're in some way making things safer/better.

They have said themselves that it generally is 20% off one way or another and even counting for that 20% tolerance it is less than 80% accurate.

As such, she had a life insurance policy.

The idea of having close to zero cash flow in Everett (without making a sizable down payment, which is not possible for me right now at least) is definitely not appealing and does not feel like a good first step to get started.