People that don't get a C/O for their rental probably haven't given their tenant a Truth In Renting booklet either and if so are in trouble with the state as well as the town.
You can find it here: http://www.state.nj.us/dca/codes/lt/pdf/t_i_r.pdf (Landlords should read it 3 times)
Not only can you get fined if you don't get a C/O, in some towns you can't even evict a tenant if you haven't registered your property with the town as a rental. The Landlord Tenant court may not accept it. This may vary by county. C/Os vary by town. Don't become a landlord unless you know what laws apply. How about Lead Based Paint addendum to the rental agreement if the house was built before 1978.
The other answers you received here are good (except for the one from Peter Rogers).
I can tell you - if you think you can fight with the town and win you are likely to be disappointed.