According to this article (https://www.newyorker.com/magazine/2022/07/25/the-haves-and-the-have-yachts https://www.newyorker.com/magazine/2022/07/25/the-haves-a

According to this article (https://www.newyorker.com/magazine/2022/07/25/the-haves-and-the-have-yachts https://www.newyorker.com/magazine/2022/07/25/the-haves-and-...) annual upkeep is typically about ten percent of the construction cost.