Everybody knows weddings are expensive. According to last year's annual survey by theknot.com and weddingchannel.com, getting hitched costs an average of $28,427 - although it really comes down to where you live. It's far cheaper to get married in Manhattan, Kan., for instance, than Manhattan, New York. Still, no matter how prepared you are to spend whatever it takes for you or your son or daughter to have a phenomenal wedding day, it may be difficult to prepare yourself for the not-so-obvious costs that come with weddings.