This isn't California. People mostly use public transportation here. Unless you have guaranteed downtown parking, driving to/from downtown for work will be more expensive than the increased cost of having an apartment near the T.

As well, driving here is not easy. Between the traffic, the aggressive drivers, the confusing navigation, the awful road maintenance and general batfuckery and the winter - you'll spend more time boiling blood in traffic than on a train. For your own mental health, I don't recommend it.

Look into one of the farther, cheaper suburbs like Braintree for T access. Or if you want to be further out along Commuter Rail, places like Lowell are affordable and walkable.