Ocean City NJ has a strict group rental ordinance requiring property owners to register with the city, to identify a responsible person over 21 who will either stay at the property or visit the property at least twice a day, and for that person to agree in writing to ensure the enforcement of all ordinances. Also, the owner must provide the names and addresses for each of the tenants. There are additional rules as well, and what this means to you is that you need to find a property that specializes in group rentals.
I do not know of any realtors in OC that have registered group rental properties, but they do exist. You can google 'Ocean City NJ group rentals' and find some, including at shoresummerrentals.com, that specify that they will rent to groups; you can also look on http://www.vrbo.com
for properties that specify that they accept groups. If all else fails, come to town and drive around In a grid, street by street, in the 6th to 14th St area, and look for signs on some of the large, older buildings.
Hope this helps,
Monihan Realty Inc,