Theres plenty to worry about when youre ready to purchase a home. But you cant let these little buggers get a pass. Pests and rodents leave different telltale signs behind. Be on the lookout for these leftovers: Rust color stains on mattress any other soft furniture, which is a sign of bedbugs. Empty brown egg sacks along baseboards and in corners, which indicate cockroaches. Cockroach droppingsblack spots typically along the back of countertops, near cracks in the walls or around electrical outlets. Dirt or grease marks along baseboards and walls, which are signs of a rat infestation.