Easy "Keys are for Cowards" Achievement
I discovered another way to exploit this achievement so I thought I'd share. Make sure you have lots of Bobby Pins then go to Rivet City. Once you get there enter the stairwell and go through the door that leads to the Midship Deck. Follow the hallways until you come to Saint Monica's Church. Right across from the church on the other side of the hall is a door labeled "Seagrave Holmes' Door". Pick the lock then go down the stairs to your left and enter the marketplace. Once you're in the market turn around and go back through the door you came from. Seagrave Holmes' Door should now be locked again allowing you to re-pick it. Continue doing this until you've picked a total of 50 locks.