White elephant

Usually, a thing which has outlived its usefulness, or is more trouble than it is worth, to the person who has it. While the item may be useful to others, its current owner would usually be glad to be rid of it. By reason of this, commercially, a "white elephant" might be available to purchase at a very favorable price.

An example of such an item might be a large, old house, occupied by an elderly widow who has neither the physical prowess nor the funds to keep it up any longer. The widow might sell the home at well below its ordinary market value because it is a burden to her. The buyer, likely someone who has use for a large home, would get a good bargain.

In Siam(?), where white elephants were sacred and had to be taken care of, only the monarch (or the very rich) could afford them, so, they were sometimes given as a present to some enemy (often a lesser noble with whom the king was displeased). The unfortunate recipient, unable to make any profit of it, and obliged to take care of it, would suffer bankrupcy and might even die.

(I'm not sure about the previous history, if someone knows for a fact to be a legend, please label it as such, or remove it. If you know it to be correct, make the necessary corrections).