Mamiya 6 checklist

I just bought a Mamiya 6 with the 50, 75 and 150 on ebay. Is there anything in particular I need to check when it gets here? The seller says it is like new and it looked the part in the photos but I have never used one of these so want to make sure I check for any hidden issues as soon as I get my hands on it!

Thanks

I have the 6 with the 50. I'd recommend shooting a test roll or two with all three lenses to make sure the rangefinder is calibrated, the frame spacing is good, and the shutters fire on all the lenses. Keep in mind the 150 has a reputation of being hard to focus wide open so it may be ok even if you get a few out of focus shots. The meter on the 6 tends to under expose but once you get used to it it's pretty good. I think the only main issue with the 6 is the winder mechanism can strip out if it's forced.

Thanks, I was going to shoot a couple of rolls anyway and I will test the rangefinder with a tripod and measuring tape or something as well.

I suppose the winder either works or it doesn't, I'm just wondering what are the conditions for stripping/damaging it? Badly loaded film or something else?