The way for you to answer your question is to see what "fees" are defined within your lease agreement with the tenant. If you created the lease agreement and the term "other fees" are not defined within the agreement, I see you have a hard time proving that the association fees are the tenant's obligation to pay.If you go to small claims court against your former tenant and lose or win, you most likely will have an unhappy tenant with you for the rest of the lease. I would try and resolve the issue amicably without having to go to small claims court.