After a tenant leaves, & you hold some (or all) of their security deposit, you have to provide/state "in writing" the reasons why within 30 days of them vacating. A good way to prove that you attempted to do this is to mail two certified letters that require a signature upon delivery. One gets sent to your vacant house & one gets sent to the tenants forwarding address. If the post office is unable to deliver it they will return it to you. DO NOT OPEN THE ONE THAT COMES BACK TO YOU. Instead, file it away & have the judge open it/break the letter's seal. It proves a few things... You made an attempt, it has the post offices date of mailing, and it has the "stated" reasons inside. Failure to do so could result in the former tenant suing you for 3x's the security deposit. Most tenants know this & they WILL win every time!