Saying that you "don't want an app for a phone" is the thing that's going to make it expensive, because SOMETHING needs to do the reading, either of a bar code or an RFID tag. The phone makes for a handy interface you likely already have for other reasons anyway, rather than having to buy some other piece of dedicated hardware.
My experience with it was that having to stop and have someone scan a tool before leaving was problematic for some of our guys, because they would often come in after hours and were alone, so they just didn't bother. So I tried to implement an RFID tag version, the problem was that RFID tags are either passive, or active. Passive tags are cheap and small, but they cannot be read from very far away, meaning the tools had to pass through a small window to be able to be read, or someone had to wand it, so back to square one. Active tags can be read from farther; that's what is in the stores when you walk through and an alarm goes off because the clerk forgot to disable it. But active tags need power, so a battery, and the battery eventually has to be replaced. Nobody wanted to do that. We stuck with the bar code system, but had an "honor" system anyway. We used TrackAbout, they offered both bar codes and RFID tags. Wasn't cheap though. If I had to do it again, I'd use a phone app.
