Cynthia Lucas did everything she could to salvage the relationship. The senior vice president of WRH Realty Services in Jacksonville, Fla., advised her client, the owner of a large apartment building, that his planned cuts in office and maintenance staff would undermine service and quality at the property. She held weekly conference calls with the owner and her own staff. She put all of the issues on the table and hoped for a compromise. None came.

So she quit. She gave the client the names of a few of her reputable competitors and wished him well.

“When you've exhausted all efforts, if you feel like it's not going anywhere, if you're not in a position where you can be successful, give them your notice with the best level of professionalism as you can,” says Lucas, who says she's has resigned from clients only twice in her 12 years in the property management business. “All of our one-year contracts have 30-day outs.”

Sometimes, it's the property manager who fires the client, not the other way around. And while nobody relishes the prospect of passing up the revenue from a property management contract, it is occasionally in the best interests of the management company and its staff to say “so long” to a relationship that has soured.

“If, when you hear their name, hear their voice, or see their logo, you don't feel very good, those are indicators that this person has got to go,” says Kathi Elster, co-author of the New York Times bestseller Working With You Is Killing Me.

Indeed, a client who has become demanding of your staff's time, critical of their performance, reluctant to pay your invoices, or stingy about providing for the property can create a “psychological drain” on employees and a real drain on profits, says Randy Shattuck, president of The Shattuck Group, a San Jose, Calif., marketing firm for professional services companies.

Shattuck advises property managers to do a twice-annual analysis of how much profit per hour the company reaps from each client. “It could be very revealing to understand that a client might be generating a lot of revenue, but they're not generating a lot of profit. If they're taking up too much time from your staff, it might be better to find a client who generates more profit.”

And factor in the psychological toll a client can take on your employees if they are verbally abusive, overly critical, too difficult to please, or needy beyond reason, Shattuck says.

Elster calls these clients the “time eaters.” “They're people who just have bad boundaries,” she says. “They don't respect your time, they don't respect your invoice.” Among the “time eaters,” she explains, are the “empty pit,” who questions everything you do; the “pedestal smasher,” who tells you you're wonderful yet finds fault with your every move; and the “exploder,” who yells at everyone.

It's not just “time eaters” who cause irreparable damage to their relationships with property managers. Susan Glenn, president of Gilbert Realty Co., a property management firm in Chicago, warns of clients who ask the manager to act illegally or unethically.