Off-street parking? In Boston? That is the funniest thing I’ve heard in weeks! XD
Seriously, I have almost been killed for parking spaces in Boston before. As for “off-street”, the only practical way to do that is to buy a house with a garage.
You might be able to make it on only $40k/yr, but you’d have to cut back on some things. For instance, expect your food costs to double. Your electric bill will be at least double as well. Rent and your student loan already push the total to $24k/yr without utilities, food, taxes, or anything else. Add in another $6k for food (and I am low-balling that one), $2–3k for utilities, and then consider that you may have other expenses like clothes, gas, medical bills, going out for a night on the town… we will low-ball those and call that another $2–3k. That is $34k net, so add another $6k for income tax, Social Security tax, etcetera, and we are talking a gross of around $40k… if you are frugal.