One final thought is, with legal marijuana in Oregon, maybe there'd be a demand for a commercial tenant in the house if it's used as a dispensary?  

Put a no grow marijuana clause in the lease.

For example I am LP in a fund that is very diversified (storage units, MF, Mobile homes, etc), a fund that specializes in taking garages and converting them to ADUs in MF, and a fund that includes a marijuana cultivation and retail store in NM.  

Nevada will be voting in November to legalize marijuana usage for any one over 18 years of age and looking at Colorado and the HUGE tax/business benefits it has brought to them, i was thinking if this passes it is a potential opportunity for huge growth.

I have been here making repairs for the past couple weeks and one of the tenants is smoking marijuana constantly with a 2 year old girl in the unit. 

The cons that I had experienced was that the tenants would smoke marijuana and complain to have things fixed.

In Toronto, Marijuana dispensaries are opening and closing monthly, the businesses are operating in a "grey area" of the law until marijuana is federally leagalize in July of 2018.

Marijuana was used repeatedly on the premises. 3.  

Caffeine’s a drug, Tylenol’s a drug, Marijuana’s a drug.

I know for a fact we could hire one investigator at $50,000 a year and they would uncover enough fraud to pay for the position 4x over.But, just like legalized marijuana, I disagree with it but I can't stop the machine.