check SDAT for tax records, or you can check the cities tax bill page here:
http://cityservices.baltimorecity.gov/
If you end up getting the property for less than its assessed for, you can appeal the assessment and pay the taxes based on your purchase price.
Looking at your numbers:
If your monthly NOI is $1018, and your rent is $1200, then your cash flow is rent minus your noi = $182/mo or $2,184 year. With $20k invested, your CoC return is about 9%. Not great. Ideally you'd want to chase deals that will get you better returns than the stock market average of 8%. Some local investors target 20% to 30% CoC returns here.
Also, I checked a local section 8 rent calculator and their rent ranges are from $1110 to a max of $1264 for a 2 bedroom. Now if you can somehow get in a LEGAL 3rd bedroom? You could get $1637. I can't tell from the listing whether or not that loft area is the 2nd bedroom or not, of if that could be converted to a 3rd bedroom.