First thing to do is Document Document Document...
Take pictures of everything inside, outside anywhere. Note all contents completely. Any before pictures you might have, include those too. Record all dates and times of occurrences however minor. If financed, have all financial records up to date. If paid for, dig out all your receipts, including any upgrades you've done. Document every phone call and conversation you have with anyone. Also, if it was in a storage yard, document that location and obtain insurance info from the proprietor even though he'll tell you he's not responsible. Do your OWN research and determine VALUE yourself. This will give you some negotiation material if everything goes south in dealing with the insurance company...we road out a tornado in Matagorda Bay Texas two years ago and our insurance company was easy to deal with.....good luck...Dennis