That's a hard one when living check to check. I know the feeling and it can be very depressing until you claw your way out of it! Good luck!
I'd sit down with Excel or a sheet of paper and figure out what payment will be comfortable for you. Also, an avg. you think you would spend keeping your current car running over the next say 3 to 4 years. Then get the ROUGH trade in value for your vehicle off NADA or KBB. That will give you a good idea of the LEAST amount of money you should take for the car if traded. I'm not sure what your payment is but I would think you could find a nice 16+ used with low miles for a decent payment. Just shop around and be willing to drive a bit. I see you are up in NJ so you should be able to snag a great deal since most everyone has locked up their pony cars for the year.
Here are a few on Auto Trader up in the 07001 zip code. Looks like they can be had for 16k and up.
I took a shot in the dark guessing a zip near you but know nothing about NJ
https://www.autotrader.com/cars-for-...&firstRecord=0
Good luck!