Hi @Olive7, I've been hosting for a while now and have been fortunate to have good guests. Since my target market are businessmen and international families I wouldn't expect them to snitch anything and thankfully never happened.
Some stuff however do get broken unintentionally - like a drinking glass but the guest replaced it with a whole set of 4. And last month's guest broke my kettle (she said they overused it due to constant tea-making and sterilizing baby's bottle) but they bought me a new one. I never had to find out after their stay, they inform me before checking out.
For your peace of mind you can set a Security Deposit to cover any possible damage to your property.
Good luck to your plan of hosting. It's fun!