Insurance is necessary, but it will not necessarily indemnify you if you have been negligent in providing a safe place for your guests.  Best practice is to have a risk management consultant do a survey of your property that you can keep on file.  This demonstrates that you have exercised due diligence to protect your guests in a professional manner.  You want to do this once per year to demonstrate your continued concern of the safety of the guests while your property.  It is likely that your insurance company can provide someone to do this for free, or for a nominal charge.

Waivers are mostly useless.  A waiver will not hold up in an injury or death claim.  The court will look at the guest's actions - or lack thereof - to mitigate damage, versus the homeowner's actions to provide a safe place to stay.  If the court determines "gross negligence" on the part of the homeowner, the insurance company usually has the right to waive responsibility for the claim.  And if they have that window, you can bet they'll take it.  That means actual damages, as well as punitive or exemplary damages, would fall directly on the homeowner.

TCB.  Take care of your business.  Your property, your liability.  Your FIRST line of defense is yourself.