@Dora31 Regarding the claim you intend to raise: when I said "Airbnb is unlikely to side with you," I didn't only mean that they won't force the guest to pay extra for the water and electricity. You're also at risk of having your listing suspended or removed for a violation of the terms of service. It's prohibited to demand previously undisclosed charges for the use of amenities that are billed as inclusive in the listing, and you don't have a viable case that use of utilities which you consider excessive constitutes any kind of physical damage.
In short, of all the actions you could take, "raising a claim" is about the worst you could do. If you don't think this issue is severe enough to merit terminating the booking, it surely can't be worth beginning the much more labor-intensive and conflict-prone process of making a claim through Airbnb.