According to the search results, the value of a ghost in Adopt Me varies depending on the specific pet. Here are the values for different types of ghost pets:

• Ghost Bunny: This pet was available during the Halloween event and could be bought from the Halloween Store for 4,000 candies. Since the event has ended, the Ghost Bunny is only obtainable through trading.

• Ghost Dragon: This pet was released during the Halloween event in 2021. Its value is not explicitly stated in the search results, but a video on YouTube suggests that it may be worth a lot.

• Halloween White Ghost Dragon: This is a rare pet that was also available during the Halloween event. It is currently worth a little more than the Heart Potion and a little less than the Quad Stroller.

• Ghost Wolf: This is a limited rare pet that was released on October 20, 2022. There is an 87.5% chance of obtaining this pet from a Wolf Box. Its value is currently about equal to the Marsh Plush.

Its important to note that the value of pets in Adopt Me can fluctuate over time based on supply and demand. Therefore, the values listed in the search results may not be accurate in the future.