Hi Larsons Mom,
Getting away from the skyrocketing prices of cable is such a liberating thing to do!
That said, I have good news and bad news. First, the good news. The Boston signals should be doable, providing you have a reasonable obstruction free pathway at magnetic 214. Now the bad, the Boston signals are in the weaker category and will need a large aerial preferably on your roof. Your concerns about having a larger antenna/and or set up are unfortunately unavoidable. Signal strengths in the low teens to single digits require higher gain and more sensitive aerials to bring them in reliably. Further complicating is your location not having line of site, which even more necessitates a strong aerial to overcome some of the quirky things signals do when terrain starts altering them.
Sadly, it is my opinion if you wish to receive Boston signals, going up on your roof is probably your best choice with a full installation. The eave mount, a link is below for a product that could work with your situation if that is your only option.
I'd recommend to you a Winegard HD 7698P for an antenna that'd cover all the bases and give you VHF capability too and likely catch other signals off the side. A smaller and UHF only option would be a Antennas Direct 91XG. You would be limiting yourself to UHF only, however it appears the Boston signals are UHF only. So, in this application a 91xg would be appropriate. The 91xg is also VERY directional so aiming it would require precision. The 91xg would allow you to target Boston and with it's narrow beam for the highest gain. I would also put a preamp on the mast with the antenna. The RCA TVPRAMP1R has performed well for me catching KLEW CBS real channel 22 (7.6 db signal strength/1-edge/56 miles) with my 91xg.
Another option might be a Antennas Direct DB8 for long range UHF reception..
I'd encourage you to consider a Winegard SW 0010 tripod roof mount mounted with an 8' pole in the most unobstructed section of your roof with the antenna looking towards magnetic 214.
It would look like this with a 91xg: (minus the smaller RCA ANT751 below)
It's not the prettiest or low key set up, however when trying to capture weaker signals, it is what the situation requires.
An eave mount if that is the only option might be this:
http://www.solidsignal.com/pview.asp...u=610370580028 with a 8 - 10' pole to mount the antenna on.
Now, that we've discussed the antenna situation. Do you plan on splitting the antenna coax to separate TVs inside the house?
Best of luck!