Tenant overstayed lease

[Evan L.]

This is a different tenant from the one in my other post. I'm trying to determine how many days to charge a tenant for over staying her lease. When lease ended( with a thirty day notice) she stayed longer moving things out. She tells me she was there only three days, but a manager texted me that he couldn't get in on the 8th day because she was there moving things out. Checked again on the 12th and she was gone with some items left behind. I don't think management did a walkthrough and they don't know when she returned keys.  

This negatively impacted my timing getting the unit ready to sell. She was also a month behind on rent, so the security deposit was used to make up for it and there is nothing to cover the extra charges. Any suggestions on determining how many days to charge her for staying past the lease?