Dear how long to keep belongings?
The City Marshal who conducted the eviction would have supervised the removal of the tenant's property to a bonded warehouse, and would have left for you and for the tenant, an itemized inventory of the contents removed.
If you chose to have the City Marshal secure the judgment by supervising a licensed locksmith changing the locks, then you assumed the legal responsibility to move the tenant's possessions to a warehouse.
You could inquire from the Marshal how to go about moving the property to a warehouse.
The answer provided to you is in the nature of general information. The general proposition being that you should try to avoid a bad outcome if you can.