Managing a Plumbing Crew's Tools Without Losing My Mind

I've been running a small plumbing outfit for 8 years now, and keeping track of everyone's tools is turning into a full-time job on its own. We use a bunch of Milwaukee M18 packs for the cordless stuff, but half the time the guys leave 'em on jobsites or mix up the chargers in the van. I tried labeling everything with their names, but that didn't stick after the first week. Watched a Roger Wakefield video where he talked about tool accountability in crews, and it got me thinking about some kind of checkout system. Anyone got a simple way to manage this without buying fancy software? The apprentices keep borrowing the Ridgid SeeSnake and not bringing it back, it's frustrating as hell. Need tips from vets on keeping the gear organized.

man ive been there, nothing worse than showing up to a snake job without the damn ridgid because some helper left it at the last house.