" When you rent a unit to a person with a disability, the Fair Housing Act requires that you accommodate reasonable requests for changes in rules, policies, practices, or services, and that you accommodate the tenant should they have a reasonable request to modify the dwelling or common areas—at their expense—to better suit their needs. Should the tenant choose to make modifications to the rental, they are legally obligated, when reasonable, to return the unit to it’s previous condition once they have vacated. "

― Brandon Turner , The Book on Managing Rental Properties: Find, Screen, and Manage Tenants With Fewer Headaches and Maximum Profits