Weird, it says it covers Boston but when I put my Boston address (single family in the city of Boston itself) it says they haven't reached the address yet.
I live just outside Boston and it worked for me (although it did consider my deck as part of my roof, which grossly inflated the estimate). Technically, they say "greater Boston area", so perhaps they don't actually include Boston itself.
Worked for me and my building is next to Copley. But Boston is very fragmented when it comes to service distribution—just see the broadband provider map:
I put in an address and it couldn't find it... Then I cleared it out and put in the address more slowly... When I did that I noticed that it found it in the drop down... so I selected it and THEN it worked... It seems like unless you put in EXACTLY what they have in the DB, it won't work... (in my case, I left off the "avenue" in my address).