It’s not very complicated thankfully, but it does require a little money and a lawyer to make sure everything is done correctly

Mixing the two sub-optimizes the strengths of house-hacking and complicates the process of BRRRR in my opinionI lay this out because the simplest approach to BRRRRing a multifamily property would be to purchase it using a commercial loan (which readily can be set up to fund the rehab AND can be paired with hard money if you're into that sort of thing). 

I considered hiring someone just to double check some of the details since it is a rather complicated master lease situation with me renting an office from my largest tenant. 

If you're goal is to eventually create a large portfolio in the US, as a Canadian living in Canada, the business structure is more complicated if you want to minimize taxes.Regarding "you can't compete in this market here", there are many cash flowing markets in Canada.

However, it is more complicated with inherited tenants, because the prior owner may not have up kept the property or told the tenant "I am selling, ask the new owner for repairs." 

I'm assuming that complicates the person who contacted me situation

Massachusetts is also a very tenant-friendly state, so if they refused to leave/pay I know the process could get complicated and costly. 

This complicates the whole QOZ situation.

But, for the "flow of money" it can be complicated if OP is doing a "hybrid split."

While it is more complicated than this, the main reason is that a turn key property like this below the FHA max loan amount does not exist in my area.