Can you take a pet deposit for service dog?

[Jack Ni]

Hi, I got a potential tenant that has a service dog. I check tenant Facebook page, her dog is a pit bull. Is it legal in all 50 states to take a pet deposit for a service dog? I usually only take $50 for pet deposit (no refundable) First time dealing with this, I will ask tenant to give me proof of documentation for the service dog (making sure she is not playing the service dog trick to avoid the pet deposit)