Income is closely related to receiving property tax credits in Maryland. In a previous hackathon project I identified which properties in Baltimore City are owner occupied and additionally which ones further claimed the credit already.
I began making maps on and off in 2013. Since then I have generated some additional maps of Baltimore from time to time.
US Census ACS Data Summary Files - These are useful for identifying the variable codes needed for attributes other than income.
Baltimore Neighborhood Indicator Alliance (BNIA)s - A good resource for data in many categories aggregated for Baltimore City