In high school at lunch one day I mentioned that I just bought a shotgun to go deer hunting with my Dad. It consumed half of my Summer Job earnings. A classmate said his Uncle gave him a rifle that he thought was a Mauser but he didn't like it. He asked how much would I give him. We agreed on 20 bucks. I bought it sight unseen. He asked if I was cheating him and I said No because that old junk was selling at the local 5 and dime for the same price.
Turned out to be Kar 98 duffle cut with capture papers. All matching. It was a double dated original WWI model, not the WWII 98K, so it really IS kinda rare.
I still have it. Shoots like a dream.