Something that happens a lot in the trades is theft. Leaving your tools on jobsites or sitting in the back of your truck overnight is a sure way to keep wasting money on new ones. Not only will other people take them if they're left out, they could get rained on and trashed even if people are honest and leave them where you left them.
The tools we use are very expensive. I bet I have $5,000 of tools in my truck at any given time. I bet I've spent over $10,000 over the years because I've lost tools, left them on jobs, or let them be stolen out of my truck. It's a stupid fucking problem to have, so it's up to you to minimize the risk.
One thing I've learned to do is when I'm on a job, leave my tools in a common place EVERY time I go to a job. I'll pick the electrical panel as a location to store everything. So when I'm done using something I put it back by the panel. Then at the end of the day I know all of my stuff is in that same area.
Another trick for not leaving, a battery charger for instance, is to put your keys on the charger. At the end of the day you'll go to start your truck but you can't. So you'll go back and grab your charger and keys and will have successfully NOT forgotten $300 worth of batteries and chargers in a random room somewhere.
One final note is to try to be more organized as a person. When you take a tool out from somewhere, put it back where you took it out of. Make your tools look the same way at the end of the day as they did at the beginning of the day. This will ensure that you always know where everything is. Also it will make sure you don't get jumped by 5 Journeymen in the parking lot because you didn't put their shit back and they can't find their tools lol.