Padlocks and how to make shims that open padlocks. If you wish to learn the combination to a Master padlock, see How to crack a combination lock or How to crack, not pick, master lock in just a few minutes!!! (does a brute force attack of one hundred permutations, not 64,000).
Locked doors and how to open them with a tie wrap (or zip tie).
The Open Organization of Lockpickers for further education.
Professor Van Helsing teaches the use of social engineering to open the locked door of the Piccadilly house in Chapter 22 of Bram Stoker’s Dracula. Later in that chapter, “a little heap of keys of all sorts and sizes, probably those belonging to the other houses” was found in the successfully compromised house. Dracula should have established a key security policy.
Check Vehicle Identification Numbers to see if they have been reported stolen or totaled at the National Insurance Insurance Crime Bureau’s VinCheck.
Clark Freshman and his interviews on Scam School [1] [2].