Back in April, the Denver Business Journalreported that a federal judge ruled one-time, nonrefundable amenity fees violated state law in Massachusetts. Denver-based Archstone lost that case, but there are other local laws out there that could ensnare unsuspecting apartment owners. Here are some key ones:

Utility Charges: Some counties have limitations on the amount of raises a landlord can administer to things like electricity and water charges. “That may be one of the things that a landlord may think they have absolute discretion to do,” says Christopher Hanback, a partner in the Washington, D.C., office of the Holland & Knight law firm.

“Back Door” Rent Control: In certain areas there has been talk about provisions that require a certain time period to pass, often a year, before rent can be raised. That can be an issue when a landlord wants to raise rents multiple times in a year to a tenant on a month-to-month lease.

Communicate: Patrick Pettitt, founder and lead attorney for Hampton, Va.,-based Sage Law Practice Group, says many states are requiring more communication with residents. “Every state continues to slowly add new requirements and new obligations, which are usually intended to force the property management company and the residents to communicate more information, more frequently," he says. Some of that information may include written receipts of payments, notices that payments have been accepted with full reservation of rights, and notices that judgments have been paid in full.

Precision Matters: When providing a written notice, remember that precision matters. “Written notices require precise use of legal terminology. A 'Notice to Pay or Quit' is legally different than a 'Notice of Noncompliance',” Pettitt says. “While use of one term over another will not create a social gaffe at your local apartment association, using the wrong terminology in documents can prevent you from obtaining the result you need. “