Does anyone know how to rid a property of rats? A friend of mine has recently moved and they can hear scratching and scuttling noises and have found droppings under the upstairs floorboards. They have a pest control expert coming but they have been given conflicting advice about them and it seems laying traps is a waste of time, as apparently rats are suspicious of new food sources. It may be they will need a drainage expert to come to try to find any 'nest' or community within the sewer. I'm not sure what advice anyone can give but anecdotes are always interesting and might point to something they haven't thought of. TIA.