First I'll disclose that I'm a commercial broker in Memphis who doesn't do apartments. However I have had significant formal training on investment analysis during my career and by teaching it in the classes offered by the CCIM Institute to standardize methods of investment analysis and to provide a professional designation as a CCIM (Certified Commercial Institute Member). I highly suggest that as a budding investor that you take some time to take at least the basic course in that curriculum which can be done online or in a classroom which is a four day commitment of your time. I have had many investors take the courses just so they develop a strong understanding of calculating alternative investment opportunities and learn how to analyze a market for forecasting rent increases or possible decreases. I would also highly recommend that you pick a specific market area to focus on initially and find an experienced multi-family investment broker to help you look at various alternatives. It can be very difficult to try to start out doing everything yourself. I am always very conservative in any acquisition analysis I do which is usually retail and if there is more than 5 tenants, I build in a property management number even if I think I can do it myself. At least I have given myself room for miscalculations I may have made instead of paring down the expenses too much. As you add more properties your experience will assist you a lot in knowing how tight you can squeeze a projected budget and how to recognize when a seller has left items out of the budgets they initially provide you. Once you're able to see either certified property records or tax filings, you'll see either the real expenses for the property or the fluffed expenses LL has included to get better tax treatment. I love finding that stuff since he's now immediately lowered the value of his property and now I guess I have to use his higher expense number in my budget!! Wow, looks like lower case flow on the property.....
Good luck in your endeavors.