Just make sure the cost of building and selling won't eat up too much of your potential profit.

In this environment I wouldn't put all my eggs in the STR basket.If your insentent on this then you must put a lot of effort into vetting the area, the rules, the property etc to make absolutely sure a given property will cashflow with conservative numbers and what your exit strategy per property is if they don't go as anticipated.

So eat life may vary. 

It is generally best to hold onto any real estate, but a condo will appreciate at a slower rate and your HOA is eating into your cash-flow, and that is not something you can control.

Dont go out to eat so much, spend less on whatever else you have to.

Building a house to sell for $400k could be a smart move if it doesn't eat up all your profit. 

You can also explore Salem or bordering areas such as Derry or hereabout but they tend to be very high tax areas so that eats away quite a bit of returns and would not appreciate as well as more Boston central locations.

They have to cover their lodging , eating out , and travel time in addition to any other expenses . 

Eat humble pie and begin at the beginning.

@Mario MartinezSell it - eat your losses and move on.