We had a lovely time at Helens place. She and her husband were extremely helpful with any query we had. Not to forget we were provided with a variety of breakfast delights every morning!
The apartment itself is gorgeous - quintessentially New England. Local amenities (including some excellent restaurants - I'd recommend Costellos) are about 5 minutes walk away. Boston itself is a 15 minute ride away and could not be easier to get to on the Orange line.
Definitely recommended, even if you're looking at visiting the city mostly.