Once you convert your personal property to rental use, it changes its use. You would start depreciation from the moment it is placed in service and is available for rental. As long as there is no personal use during the time it is a rental, you would depreciate the entire amount. If you were to convert back to personal, then depreciation stops.
Placed in Service
You place
property in service in a rental activity when it is ready and available for a
specific use in that activity. Even if you aren’t using the property, it is in
service when it is ready and available for its specific use.
Example.
On April 6, you purchased a house to use as
residential rental property. You made extensive repairs to the house and had it
ready for rent on July 5. You began to advertise the house for rent in July and
actually rented it beginning September 1. The house is considered placed in
service in July when it was ready and available for rent. You can begin to
depreciate the house in July.
