The overall wear and tear on everything in your rooms. Puzzles, props, locks and keys wear out when you get a lot of traffic so keep plenty of backups. Based on the complexity of your room, that can get expensive. Backups and easily replaceable items are a must. At some point most things disappear as well. Anything that fits into someone’s pocket at some point will walk out the front door with them… players get so immersed in the game play and excitement and will forget about it. A room inventory checklist needs to be your Clue Masters best friend.