Brent, when looking at Krags and 03s, hold the rifle lovingly, close your eyes and work the bolt a couple of times. Your fingers will tell you which one to buy.
Some Krags have cracked bolts. What you look for is a crack behind the locking lug. No need to go into magnafluxing or such. Either you can see it or you can't. To me, chip out of the rim or collar around the bolt face is not a big deal, just evidence of abuse. The crack in the bolt should knock about $80 to $100 off the purchase price, but it should not be a deal-breaker. Replacement bolts are pretty easy to find.
When looking at a lot of Krags, my left thumb gets sore from pulling up on the extractor just before you turn the bolt handle to remove the bolt. I have taken to using the handle of an old toothbrush to lift the extractor.
Also, be on the lookout for conversions to .22 LR. They are rare but they do exist. I have played extensively with one that was turned into a pretty nice sporter. They look almost like every other Krag. If you find one, be sure to let it distract you.