For my job, I use lots of tools. If I'm going into a situation, and I'm not sure what I'll need, I usually take channel locks, a couple screw drivers, and a crescent wrench. Those tools can take care of most minor maintenance.
Another tool that's proved vital for my entire career is the multi-tool (i.e. a Leatherman or Gerber). I carry mine in a pouch on my belt, and it's always readily available whenever I need to tighten or cut or pry something. When I was at Nellis, I got issued so many of these, I never had to buy one. Over the years, however, they've been lost or stolen or offered as a sacrifice to the plumbing gods if only this damn faucet would stop leaking. The last one I had was a Gerber 800, and I loved it. It was issued to me six years ago in Japan, and I can't believe it's lasted so long.
That is, until Tuesday.
MSgt Lewis and I were investigating a water leak, and I was using my Gerber to pry up a valve box cover, when...SNAP! The handle broke. I couldn't believe it.
Now I'm debating whether to buy a new one out-of-pocket or wait and see if I can finagle one out of the Air Force. Even if my squadron decides to purchase them, they'd have to buy them for the entire shop, and the paperwork could take months. I'm just not sure if I can live without it that long.