Rental Home conversion to personal for one calendar year, than back to rental

[Anonymous]

Purchased the home in 2008 and has been a rental since then. At the end of 2018 my daughters roommate moved out. We never replaced the roommate and did not increase my daughters rent for the year of 2019. Hence, the rent we received for the full 12 months is now considered under fair market value. Starting 2020 we are back up to collecting fair market value rent. 
How do I change the house to personal basis for 2019 and then resume as a full time rental staring January 1 2020? I assume we lose the ongoing depreciation for the year 2019 when it was considered personal business, but need to resume it all starting in Jan. 2020? Thanks for any suggestions you have. Can this be done on TurboTax?