Eligible Mortgage interest on a rental property converted from primary home which had cash out refinance

[Customer1001]

I bought a primary home in 2013 with 600k loan. I had the brought down the loan amount to 100k in 2015.Then i did a cash out refinance in 2016 to bring the loan amount to 800k followed by another cashout refinance in jan 2018 to bring the loan amount to 1.1m. The cashout was not used for home improvement. Later in june 2018, i converted the property to Rental. How do i calculate the eligible mortgage interest for the rental duration (that i can claim as expense)? Since at the time of rental conversion my loan amount was 1.1m, do i consider the loan amount to be 1.1m and caculate interest paid for the rental duration? Or would i have to use 600k or 100k or 800k as the loan amount? 

[MarilynG]

In the Rental section, enter the % of the total amount of Mortgage Interest reported on the 1.1M loan that was used to finance the home.  You don't have to enter a Loan Balance in this section.

Based on the date you indicate you started using the property as a Rental, TurboTax will calculate the amount of Mortgage Interest to move to Schedule A, Itemized Deductions for you. 

Since your 1.1M loan was not closed prior to December 16, 2017, and the amount was more than the 800K loan it replaced, you will be limited to Mortgage Interest up to 750K.

Here's more info:

https://ttlc.intuit.com/replies/6012857