Can I drive a car home with no tags in NJ if I have proof I just purchased it from a private seller?

You Need tags. Cheaper  than a ticket.

A "friend" had his smog system repaired on his car, it was registered in another county, Guess What--Last night (12/17),  the mechanic tried to drive it a few miles to check his work, he got a Ticket for expired plates!

Now, my "friend" needs get a 30 day AND pay the 'wrench the fine as well as the repairs...a  missing fuel pump gasket  suddenly cost $125 More..

@Robert: Bull Crap. My "experience" above shows  you Won't. Besides, just being detained  IS an Arrest. Someone carrying signed-over title in car at the time is plenty of proof car not stolen. Cops can Call the previously registered owner, Anyway. 

No.  You need to have valid tags.  Temp tags are not hard to get.

Any and all of those are possible and probable. Temp permits are easy to get

Check the NJ DMV website for a permit to move a vehicle after purchase. (VA has this method in place. NC makes it PIA so each state varies). It costs only a small amount all you need to do is put the permit in a window and INSURE the vehicle and you would be allowed one trip to move it from the sale location to your location of choice.

We can't possibly tell you what may happen.  Maybe a psychic can?

If it were me, I would insure it and drive it home sans plates.  I wouldn't worry about it.  If you are worried, insure it and buy Temporary (transport) plates from N.Y.

You'll likely be okay. I write a check to the DMV for the license plate fee and have a check book with carbon copies of the checks I write so if I happen to get pulled over I can show the cops I paid for the plates and am waiting for them in the mail.

If you get pulled over driving a car with no tabs your car will be impounded and you will be arrested.Have fun.