When I went to remove my block heater this fall that's when I realized I didn't have a 32 mm socket with 1/2 drive. Needless to say, now I have every socket to 40mm, because I went out and bought them, used. It was a good buy. When I went to do my Power steering pump on my Volvo, I realized there was a special tool to remove the pulley. I know own it. When I went to fix the vacuum dampers on 87 300D climate control, thats when I needed a Mityvac, even though I had a standard hand held vacuum pump. So I got one. Similarly, I went and got my own radiator pressure tester and three types of spring compressors last year after one set shifted on my 87 300D. I always try to pick these up used. Do I regret this habit? Not really, for the most part I never buy these tools new, so I save 50%. Granted the money you spend on them adds up, but after spending 10 years jury rigging this and improvising that, its an obsession to always have the right tool. Now what scares me is with the OBD II scanners and Laptop diagnostics and laptop reprogrammable ECU fuel management tools on the new gassers, I may be headed to a new level of ridiculousness...but I a guess I'm not the only one with this obsession... The only thing I do pass on is Air Tools. For a lot of wrenching, you just can't get them to the point of access, and after a while I just get lazy and stop using them...