BiggerPockets also has a calculator to analyze deals, and I highly recommend you start this as soon as possible, even if you are not ready to buy.

When you finance through national lenders, in your experience, is a balloon a common requirement for commercial loans of this nature or is it possible to get a fixed rate for 30 years?  

I would say you need to play to your strengths, whatever those might be.

You could have used that $8800 to possibly have partnered with someone locally that is already doing the subject to deals to figure it out first hand.

It is a very safe play.

Not sure if the upstairs tenant (heavyset person with a dog) plays a role.Seeking suggestions.

@Drew Sygit brings some good insight into the possible pitfalls.

Quote from @Jason Malabute: A 1031 exchange is possible.

Comps to me no longer play the only role because of rates, seasonality, etc., it definitely fights the arguments on re-fis with the appraiser but I'm noticing there's just a liquidity issue that is skewing things.I try to essentially start at the floor and work my way up on the ARV as opposed to seeing the highs and working it down.

Generally speaking, Boston proper is an appreciation market (low cap rates) unless you have a solid value-add play.