Rats live in any situation, which provides food, water and shelter. It is found in both urban and rural areas. In the homes they will live in lofts, wall cavities, cellars and under floors. In the gardens they will burrow into compost heaps, grassy banks, under sheds and are commonly found in sewer systems. They carry germs and disease, salmonellosis (food poisoning) and weils disease, which can kill. Rats breed rapidly, they can chew through most things including cables. You won't just have one.