What would be the "available date" for a house that was partially rented/residential for 3 months and converted to rental in the last 3 months. 6 months ownership in 21

What would be the "available date" for a house that was partially rented/residential for 3 months and converted to fully rental in the last 3 months. 6 months ownership in 2021. Also, do I divide property tax/interest by 2 for schedule-E or enter the whole amount and Turbotax will divide it for me?