Tremont is an excellent area with really high market rents and super high demand.  5000+ sq ft. is huge too, congratulations!

As an aside, insurance companies are inspecting most properties one way or another in the current market. 

I avoid the multi-family market here, so unfortunately, I will not be a good go-to here, but I am confident you will find quality resources and help here on BP.  

If looking to change the market value of property, well there you go. 

After living through the GFC and the shrinking market for local banks, they saw an opening in the market for what they call "consultative banking" like they had years before and decided to start a bank.

Just be sure to account for the upfront costs, ongoing maintenance, and market demand to make sure the numbers work for you.Good luck with your decision, and feel free to share updates as you move forward!

You can achieve or even exceed your current cash flow in markets that are more landlord-friendly than Boston.

Get familiar with price points in your market and what looks like a good deal. 

I'm a local realtor and would love to connect and chat about the local market.

Leverage your W-2 income for better loan terms, explore private/hard money for off-market deals, and network with investors to expand your deal flow.Good luck!