Beyoncé and Jay-Z: $4 million

For their ultra-private nuptials on April 4, 2008 (deliberately chosen to match the couple’s obsession with their lucky number, 4), music’s ultimate power couple completely bypassed a public venue. Instead, Beyoncé and Jay-Z transformed his massive 8,000-square-foot Tribeca penthouse in New York City into an impenetrable, top-secret sanctuary. Though they limited the guest list to just 40 close friends and family members, costs quickly escalated to seven figures. The primary driver of the budget was the decor: the couple imported 70,000 pristine white dendrobium orchids directly from Thailand to drape the entire industrial loft space. To maintain absolute operational security, guests were famously forbidden from bringing mobile phones or cameras, leaving the public with only brief, nostalgic glimpses of the ceremony in later concert tour footage.