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ROI and Cap Rate.......On a 20 unit I'd expect to get rent roll and financials. I always take these with a grain of salt though. Then do your evaluation.....is it in an area where rents will increase or decrease? Is there high turnover or steady tennants? What's the vacancy rate? Is it in an area that is appreciating or depreciating? Who's responsible for the utilities? Is there a chance to make any improvements and increase the rent. Typically buildings like these sell for purely a function of the rent, so if you plan to sell it for a profit in the future you will need to evaluate how you can increase the revenue. Is there a chance for laundry, vending, condo conversion, build additional units, etc.