How to find an apartment without cockroaches?

Have your landlord call the exterminator. It will take a couple of visits. Most buildings have a contract with the exterminator and they will come in montly to do a preventive spray or traps etc.

You will still get an occasional roach sneaking out of your drain even if they have plug/barriers. It is virtually impossible to control that in my experience. You should be able to control roaches in your kitchen completely by keeping it clean and monthly preventive visits by exterminator.

5 cockroaches in 9 months is NOTHING in any major city, whether the building is pre- or post-war. Consider yourself lucky.

>>really great and wealthy Manhattan neighborhood<< makes no difference if mgmt is sloppy with prevention. Are you on a lower floor? That can sometimes make a difference.

An ultrasonic pest repellent might help. You can get it on Amazon.

Plus it makes a big difference if there is a restaurant or grocery in the building.