Hi there, generally a CO is required to close. Unless this is a short sale/bank owned home that is "as is" with buyer responsible for getting the CO, this is usually the responsibility of the seller, to arrange and pay for.
Townships have specific requirements - whoever (ie, Seller or Buyer) who is responsible for getting the CO, should speak to the town directly. It usually involves an inspection by the township fire bureau to test Smoke Detectors, Carbon Monoxide Detectors, and Fire Extinguisher for compliance, function, and placement.
Good luck to you on your closing!
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