In a nutshell Your cost-basis is the "LESSER" of what you paid for it, or the FMV at the time the property was placed in servce. Then to that you add the cost of any property improvements. Then from that total, you subtract all depreciation taken on the property. If you've been reporting this rental in TurboTax since it's been a rental, then when you report the sale on SCH E, the program will take care of all this automatically.
