Yes, it is. Coop boards hold great discretion in whom they select to be their neighbors. Not only are the financial viability of the applicants considered, but the relative close proximity and interaction each neighbor has with each other is taken into consideration. I've heard rumors of applicants being turned down for having large pets, for social reasons, because the applicant is purchasing for investment only, or because the applicants gave the impression that they'll be difficult or have horrible personalities. Each board is different in their standards, but the interview process is "par for the course". Condos are an attractive alternative for many first-time home buyers, buyers with a sketchy credit history or buyers that don't want the intrusion into their personal and financial lives. The benefit of coops are that that a buyer tends to (generally) get more square footage for their money and the coop community is stable and financially viable.
Most Co-ops follow the same procedure with the application and the board interview, BUt they are not all the same. Some are stricter than others. Unless you are buying a sponsor unit or a condo, the process can take longer since your neighbors, people on the co-op board, would like to know if you can fit within their community. Good luck on the interview and relax it's just a formality in many co-op boards.
Have a Happy New Year!
Vice President Associate Broker
The Corcoran Group
646 593 7207
Licensed Real Estate Salesperson
Unfortunately, co-op boards wield a tremendous amount of power, and have the freedom to reject people at their discression regardless of whether or not the person is financially qualifed. It's a terrible system. I went through it myself when I sold a co-op in Manhattan years ago. What you're going through is not at all unusual, just annoying and frustrating.