It showed this old Caucasian guy, but during the call I noticed by his action that he is African American. 

It's an American problem @Ben Daniel .

Sometimes we need to just rely on a good old fashion "Bluff".Write them a letter (All tenants of the building)  stating that you have had complaints regarding the smell of pot in the building.

My observation and research as a non American investing in America is thet your appreciation is the least predictable of any western nation.

Education has become totally devalued by American society.

All fine and well if you like to give money away in that fashion. 

Quoted from the paper:—Reveal’s analysis included all records publicly available under the Home Mortgage Disclosure Act, covering nearly every time an American tried to buy a home with a conventional mortgage in 2015 and 2016.

Either your underwriting is too aggressive or you need to get your inspections done in a timely fashion to comply with contractual obligations.Good luck

I am an American living in Costa Rica.

Please reply in some fashion to let your interest in this be known.