@Priscilla273 always put something in your listing/house rules that guests may encounter insects on your property. That is the only way to cover yourself if you get a complaint.
Most rational humans would expect to see an insect once in a while, even indoors. In our region bugs are part of the deal. But every now and again you get a phobic guest, or a guest who comes from a desert region, or just an out and out "I want a free stay/I want my money back because my friends are staying elsewhere and its too late to cancel" guest who will abuse the system.