A branch of a hamburger chain opened in the building next door to my co-op. Now, apartments in our building smell like burned grease. It’s worse in the spring and summer when windows are open. Some of the residents approached the manager of the restaurant, who promised to install a filter on the ventilation. That was two years ago. We have filed complaints with 311, with no results. Do we have any rights? Is there anything we can do so our apartments don’t smell like grease?  Living next to a restaurant has its upside: speedy deliveries! But you and your neighbors have discovered one of the unpleasant downsides: the cooking odors. (Noise and vermin are the other chief complaints.)  Your co-op board should step up and advocate for its residents. After all, this is a problem that affects multiple residents who should not be left to battle the burger stench on their own. The board could start by contacting the owner of the neighboring building and pointing out the obvious: There might be a problem with the restaurant’s ventilation system. Perhaps the restaurant could (and should) invest in a new one — or at least install that filter the manager suggested two years ago. The restaurant’s lease may include a provision requiring it to limit cooking odors, and your board could insist the neighboring building enforce it, said Lorraine Nadel, a Manhattan real estate lawyer.  Submit your questions, share your stories and tell us what topics interest you most. Post a comment or email us at realestateqa@nytimes.com.  If the problem continues, the board could file a private nuisance claim against the neighboring building. But it would have to show that the restaurant’s use of its property constitutes an unreasonable, intentional and continuous invasion of the co-op residents’ property rights.  “Everyone has a right to the use and enjoyment of their home,” Ms. Nadel said. “An offensive odor emanating from a neighboring restaurant can constitute a private nuisance.”  I have lived in my co-op for over 26 years. Over the last several years, I have seen large water bugs in the bathroom around the sink on hot and humid days. The exterminator and managing agent found no gaps in my apartment’s pipes and they were flush with the walls, so the bugs shouldn’t be able to get in. The exterminator says that when the weather is rainy and hot, they climb up through the pipes. Therefore, there is nothing that can be done to ameliorate the issue. Is this true?  Even the most hardened New Yorkers might recoil at the site of a colossal American cockroach, commonly (and incorrectly) referred to as a water bug. Unlike its smaller cousin, the German cockroach, the American roach rarely takes up residence in city apartments. It prefers subterranean habitats like sewers, boiler rooms and manholes. But as you have discovered, it does make the occasional appearance on a kitchen counter or bathroom floor — particularly when it is warm and wet.  But you need not resign yourself to sharing your apartment with the supersized bugs. “They’re not really living in your apartment,” said Gil Bloom, the president of Standard Pest Management. “You’re getting the overflow from somewhere else.”  Your drainpipes have a U-bend that should, theoretically, keep the pests out. Sometimes, particularly if a resident is away for a long stretch, the water that sits in the U-bend can evaporate, clearing a path for the roach to climb into your apartment, Mr. Bloom said. One solution, he said, is to place a piece of tape over open drains. You could also place glue traps beneath the sink and lightly dust boric acid under the sink and in crevices, keeping it out of reach of children and pets.  Although a visit from a single American roach is not necessarily a sign that more will follow, if you see more than the occasional one, it might be a sign that there is a moisture issue or a problem with the sewer line in the wall. Building management is obligated to keep your apartment free of pests and should not dismiss this as a fluke.  “These insects are not coming from the thin air. There is a nest somewhere,” said Jack Erdos, a Manhattan real estate lawyer. “If the building’s current exterminator is unwilling or unable to do the job, the building has to hire an exterminator who will.”  Doubling Down on the Broker  We are considering selling our apartment and buying a larger one. Are there disadvantages in using the same broker to sell our current unit and buy our new one?  Buying or selling an apartment is among the more fraught of life experiences. You’re handing over (or receiving) an enormous sum of money and taking a leap of faith that the decision you just made was a sound one. Working with a single broker — specifically, one you genuinely like — can take at least some of the pressure off.  “If you ask me, it’s the only idea,” said Gary L. Malin, the president of Citi Habitats. “Having someone that you know understands you, looks out for you, it’s almost priceless.”  Swapping apartments gets complicated. Once you sell your home, you may have to negotiate a rent-back. If your apartment sells for more (or less) than you anticipated, that could affect your next purchase. By working with one broker, you streamline the process. “Having a single advocate with a 360-degree understanding of your lifestyle and needs will allow that agent to deliver the best level of service possible,” said Ari Harkov, an associate broker with Halstead Property. You might also be able to negotiate the broker fee, since two commissions will be involved.  But there are potential pitfalls. If you are leaving Manhattan for another borough, for example, your selling broker might not be familiar with your new market. Also, not all brokers handle both sales and purchases. So if your favored selling broker does not generally work with buyers, you might want to reconsider using him or her for both transactions.
This week’s subjects include cooking odors from next door; bugs in the sink; and using the same broker for buying and selling.