What is the ruling on transporting a deceased person from non-Muslim lands in a coffin and then burying them according to Islamic law, or burying them in the coffin itself, and what is the ruling on selling the coffin and what happens to the money generated from its sale?

It is disliked to bury the deceased in a coffin unless there is a need for it, such as the unavailability of bricks (for the grave's structure), softness of the earth, or decomposition of the deceased, due to the extravagance involved and because it is a custom of non-Arabs. If the deceased is not buried in it, there is no objection to selling it and benefiting from its price for its owner, or for the deceased's heirs if it was the property of the deceased.