Visit the buildings you are considering and see for yourself. To find out, go through every room in your home, focusing on the kitchen and bathroom, where pests are usually worst. You may need a flashlight for the dark areas. Cockroach droppings look like dark smudges with dark dots. Their egg cases are yellowish and ribbed, about the size of a small fingernail. The most conclusive sign of a cockroach infestation is simply seeing them in the home, but because they are nocturnal insects they are not always easy to spot. Luckily, roaches also leave a tell-tale odor as well as other signs of infestation. The more severe the infestation, the more cockroach sightings are likely during daylight hours. This is not the case 100% of the time, of course, and regular daytime sightings arenâ€™t that common for minor infestations. Given that cockroaches are nocturnal and normally stay hidden during daylight hours, knowing how to recognize other signs of cockroach infestation is essential. One of the most common signs that cockroaches are present in the home is the presence of what are known as shell casings. These are egg cases from recently hatched cockroaches, and appear as small dark brown oval-shaped casings. Another common sign is the presence of cockroach specks. These dark-colored specks are fecal pellets and regurgitated food, and look like grains of ground pepper.