What is the Fair Market Value of Your Rental (Including land)?

No, this question is referring to the value of your rental unit, not the rent. 

This is usually the purchase price plus any improvements you made that substantially increased its value from the time your purchased the home and the date you placed it in service as a rental. 

If the rental property's estimates value (from Redfins, Zillow) has changed since the purchase data, would it affect the FMV?

You use the LESSER of the FVM at the date the property was placed in service  OR  the current market value ... I highly doubt the current value is less in these market conditions so it would be a non event.

thanks!