@Sarah6096 Firstly Aircover for damage is not an insurance product so absolutely cannot be relied upon. Also it only covers you for damage caused by a guest (at best) so if the house burns down between guests you would have no cover. It also pays a depreciated value rather than new of old that most proper insurances provide. Finally by short term renting you may well totally invalidate your household policy.
Please talk to a broker like JL Morris to see what they offer and also check with your insurance to see if your current cover is invalidated.