What is the 1099 k form I need to report rental income

[MaryK1]

If you received rental income by credit card or other third party transactions, you will receive a 1099-K.  Not everyone receives a 1099-K so you may not have an entry.

A payment settlement entity (PSE) must file Form 1099-K for payments made in settlement of reportable payment transactions for each calendar year. A PSE makes a payment in settlement of a reportable payment transaction, that is, any payment card or third party network transaction, if the PSE submits the instruction to transfer funds to the account of the participating payee to settle the reportable payment transaction.