Hire Professional Guardians
It may sound silly, but an armed guard or two couldn't hurt when it comes to keeping your grandparents' marriage certificate safe, right? Consider renting a safe deposit box at a bank. Although the men in black probably are more concerned with guarding all that cash, you'll still get the same protection for your documents. Typically, the metal boxes aren't expensive (about $30 to $75 a year) and have the added bonus of being housed in a bank vault that's pretty unlikely to be damaged by a fire or burglars.