Our office houses realtors, wholesalers, mortgage companies, contractors... 

However, I don’t have a US-based W2 (but work full time for an American tech company in their London office). 

Consultants, inspectors, and mentorsProperty managersAssistantsBookkeepers, accountants, and attorneysLandlords if you rent your office spaceYour business partners if you paid them (except if they were strictly lenders)Disclaimer about wholesalers: it is a controversial issue, with some of my colleagues claiming that wholesalers do not need 1099s.

actually most of the family office type folks I work with have little debt and LOTS of cash to invest... depends on where your assets are ... are they quality assets or subprime assets. it also depends on your make up.. 

@Tayvion Payton to get a better understanding of the loan products, it's best to have a conversation with a commercial loan officer at a local community bank or credit union.On commercial, the number one rule is a deal meeting their DSCR loan covenant, which is typically 1.2 to 1.25. 

So I contacted the tax collectors office and was told there was a legal loophole and that since the building had been owned by a non-profit for part of the year it would receive tax exempt status for the full year.

Which isn't necessarily terrible except the corporate offices for the DG/FDs of the world only looked at the bottom line numbers, didn't care about the condition/quality of the workplace, and most stores are not in great shape. 

Make sure you talk to a Banker or Loan officer that is well versed in both SE (Self Employed) income and also Non/QM programs.One tip I will give you as a Banker is open up a "Business Checking account" and for the next 12 months pay "Everything" out of that account. 

Brokers will be eager to add you as a new agent to their office.

Finally, check with the Town to make sure there are no municipal liens, Make sure they're on Town sewer, check with the tax assessor to see how many bedrooms the tax office thinks there are, (important if you are flipping) buy ok to have more bedrooms if you are planning to buy and hold.