If you are looking for 'Rental Insurance,' you need to know that it is a type of Travel Insurance.
Travel Insurance WILL NOT PROTECT YOU against FRAUD. Possibly paying through PayPal or some other methods might protect you from that, but the biggest thing is to do Due Diligence and find a member who posts on these boards or who you can otherwise vet and verify.
The purpose of Travel Insurance is to provide Emergency Medical coverage while you are traveling, AND provide you with most or all of your money back if you need to cancel for covered reasons, or if you can't travel for covered reasons. But make sure you know what those covered reasons are. They do not cover as many things as you might think. So read the fine print very specifically AND use their communications and chat features to help yourself understand it.
The best all around Travel Insurance clearing house that I have found is Squaremouth (
www.squaremouth.com ). They have dozens of good, reputable insurance companies with hundreds of different travel policies. Keep looking until you UNDERSTAND what you want in Travel Insurance, and until you understand exactly what the companies offer.