If I were a property owner I would absolutely be concerned about the damages that can be caused by an animal. Especially if I’m going to be paying for carpeting, lawn care, etc. In this aspect I would charge quite a bit for an animal, but at the same time in a renters perspective, it must be affordable. A lot of people have pets and unfortunately a lot of places don’t allow them. I would stick with maybe 100–200 dollars deposit and maybe $20 per month if you want to add a monthly fee.
Also… please please don’t discriminate against types of animals, or animal weights. So many places have a list of dog breeds that aren’t allowed, and I think that is absolutely bogus since any dog can be a good dog depending on its upbringing.. and it doesn’t matter if your dog weighs 10 lbs or 100 lbs, if it poops on the carpet – it poops on the carpet. Weight doesn’t determine a good dog.