I would live somewhere where you can take public transportation. You want to be on the green (D or E) or orange line. Parking costs for staff are astronomical to park at a satellite lot. At my last job (I was on site at the hospital but worked for an outside company and they reimbursed my parking), parking at Simmons College cost over $300/month. That was 5 years ago so I'm sure it costs more now.

When I was employed by the hospital, I took the D line when I lived in Brighton and the 39 bus when I lived in Roslindale. Nowadays when I go there I still leave 45 minutes (or more depending on time of day) to get there and I live exactly 5 miles away.