France Fishing Gites

I'm starting to understand the complex world of insurance for gites after almost 3 years!! On the basis that it's the CUSTOMER who must have the relevant insurance for damage, fire or flooding it is not a problem for my French customers as I always ask for a copy of their insurance, and am confident that my insurance company would claim off theirs (thankfully never happened yet!). However, for English (or any customers who are not French) that is not the case. And no amount of security deposit would cover someone leaving a chip pan on the cooker and burning down my gite. I've been wasting lots of time on the phone to UK Home and Travel insurance companies to find that no-one appears to offer the right level of cover for British people to insure against risk in a rental property abroad. I have found a French company that does have a web page in English (Aduciel/Adar) that I'm sure my customers can use to take out the relevant policy (not too expensive either), but wondered if anyone else knew of any others (as I'd like to offer the choice of more than just one) or if anyone has found a UK company that does give the relevant cover. Hope this makes sense!!