The lease agreement. The lease agreement you give to your tenants is your guarantee that they won't damage your property and that they will pay their rent always on time. But, if you've decided to make your property pet friendly, you can include a special clause in the agreement specifically targeted to the possible damage, done by the pets. There you can establish adequate penalties and fees for kinds of damage, consult it with the tenant and a legal advisor, and sign it.

Security deposit. When you allow pets in your rental property, you should have in mind that even if the pet is well trained, it's possible that there will be damage. As a landlord, you have the right to demand a special non-refundable pet deposit, which will cover the expenses around the repairs you'll need to make after the end of lease. This way you won't have to worry too much if your apartment is being damaged.

Limit the space. Also, one good way to limit the damage done by pets in your rental property, is to limit the space the pet will be allowed in. For instance, you can make the bedrooms forbidden for cats and dogs. Or, if you're really worried about your property, you can allow pets only on the terrace or the balcony, if they are enclosed somehow and secured. It all depends on your own preferences and beliefs.

There are not many landlords who would agree to give their property for rent to people with pets, so it will be an advantage if you do. Just make sure that you're prepared for the possible damage done by them.