The map above comes from real estate listings site Zumper. It shows the median one-bedroom apartment rents in Boston for the spring (an interactive version can be found through here).
The figures come from active listings—vacant or otherwise available apartments—so it’s a pretty accurate snapshot of what a one-bedroom place in the city will run you.
The redder areas, including the South Boston waterfront and Back Bay, are the more expensive areas; and the lighter areas such as Roslindale and Mattapan are the less expensive ones.
Also: Here’s more from actual tenants on what they pay in specific areas of the Boston region. Good luck.