http://www.nj.gov/dca/divisions/code..._srvy_2009.pdf
if it says 3+ for units for example, it means that at least 3 units need to be owned by the owner.
for some you have to look deeper into it, for example...renting a condo from a person in one town will not have any rent control on it, in other towns a condo that is rented will have rent control put upon it automatically.