The ideal situation will do it as homeowner builder instead of getting a contractor. 

If so, what size developments are you looking for 1-to-4, or something larger? 

Ideally, the Post Office keeps leasing it as a Post Office. 

Great Boston is still ideal from the distance point of view, but the inventory is almost nil, crazy-priced and mostly antic.Deliver at least 5% ROI yearly after all expenses (taxes, management, insurance etc.)

I have found these smaller, regional banks can be more open to development and investment backing than the bigger names.If you're looking for individual contact names/#'s, PM me and I can send you some.

Ideally, in a BRRRR strategy, goal is pull as much cash out as possible, or even have no cash invested at all after the refi, but since this deal may require keeping some of my capital engaged, not a perfect BRRRR strategy, but still offers a good ROI from an "equity gain" perspective and also from a cash-on-cash flow perspective ($350+ per month).

this is the ideal scebario as you can now renovate and put in a good tenant at market rate. inherited tenants are usually paying below market and not screened to your standards

So, lots of money (and Fremont has a lot) plus serious lack of new construction SFR plus still historically low interest rates mean something like this is a great deal for a developer, and actually not that risky a bet. 

After acquiring floor plans what is the next steps to getting it built?

Plus, there's major development happening in the neighborhood and values are going up about 10k/month on the SFH.