The Robert A.M. Stern-redesigned 12th floor of 820 Park Avenue is so fancy that the dining room walls are now made of gold. Well, okay, that might be wallpaper, but still...pretty fancy wallpaper. Going by previous listings we've seen come out of 820 Park (what is it with this building?), the redesign was probably a pretty good call, and now the apartment is asking $16.5 million after selling for only $6.5 million in 2008. No word on the total square footage, but maintenance is a hefty $9,061.