I have a gain on a sale of a rental property. That section of turbotax isn't available until 2020. Can I enter the gain elsewhere to model the effects of the gain?

[smarttees]

A calculator is here 

[LeonardS]

No, it is not recommended that you enter information in TurboTax where it is not intended to be entered.  If you enter "test data"  in a field to bypass the normal entry this may cause the input to be incorrectly calculated.   You also run the risk of forgetting to delete the "test data"  when the proper data entry can be made further causing potential calculation errors. 

The link IRS forms availability table for TurboTax individual (personal) tax products will provide an update on available TurboTax forms.