Another broker from Maryland advised me to be very, very sure of the apartment before I actually buy it. Numbers don't cover the whole essence of the deal. He even asked me to input the data into a free property analysis tool, which calculates real estate cap rate, yield, gross rent margin, cash flow (before and after tax), and rate of return, among other things. I keep walking around asking, do I know the vacancy rates, the rent, expenses, and property appreciation rates? This would be a good time to mull over.