60 $5 wrenches doesn't help the attacker if I'm not physically on the same continent. Attacker needs to know where you are and have physical access... and as we all know, once you have physical access, it's game over :)
Remember: you'll be hard pressed to buy a quality wrench for 5 dollars, and - perhaps more importantly - why are you breaking them in the process?!
I suspect your process should use the wrench on lower wear items than computers, for example the desk (if plastic or wood) and things sitting around it.