• A roommate's possessions. Unless you want to document all your roommate's possessions and have them added to your policy, they're going to need to bring their own insurance to the table if they wanted to be protected in the event of damages or theft. However, a roommate might be covered if their possessions are documented, and they are a member of your family.
• Exterminators and damages caused by pets. This is an exclusion on most home insurance policies as well. Unless you buy additional insurance to protect you from the costs of dealing with an infestation, you can't expect renters insurance to handle the problem for you.
• Flooding. This is another exclusion that renters policies share with those of homeowners. Unless you specifically buy flood insurance, your policy won't cover it.
• Your car. An auto is a possession, but it's not exactly in the same category as an Xbox or silverware. So, you can't expect your renters policy to cover it. Thankfully, that's what car insurance is there for.
• Any undocumented possessions. Keep receipts and photos, and make sure your insurer has a copy.

Renters insurance only covers two fronts: the renter's possessions, and certain liability claims. These policies don't have to do the heavy lifting of a home, auto or health plan. So, the good news is that they tend to be affordable. Your landlord's insurance will cover all the big expenses. That way, you only need to worry about covering your own end.