I sold a property once that included a new furnace that was not installed. It was in the original carton. The seller purchased with intent to install, but never did.
My investor buyer purchased the unit, sold it 1 year later......with the same furnace in the same box.
I didn't rep the buyer on that transaction, so I don't know whatever became of the furnace.
The installed existing furnace went through 2 inspections with me and was found to be in good working order.
All info was fully disclosed.