I also had to take a LL to court over the deposit.
In addition to EconProf’s very good recommendation (the list), it’s always a good idea to take pictures and video of the ENTIRE property — inside and out, including the garage, yard, driveway, etc.
Lock the pics/video/list away in a fireproof safe, just in case you need it in the future. As part of the video, tape something that is applicable to that day (like a shot of a TV show with date clearly stamped and/or newspaper from that day). It’s not 100% proof of the date, but can help, IMHO.
