how do you know if you have rats in your walls?
['Squeaking or scurrying sounds in the walls.', 'Running or soft footstep sounds primarily at night.', 'Piles of droppings in an area behind a stove, in the basement or attic, or on the ground.', 'Food packages, containers or wooden spoons that have been gnawed on.', 'Rub marks, which look like an accumulation of dirt and grease.']