[@Searat]
The knives are made of cheap metal, not even iron. Probably tin or pewter. That being said this boy seems genuine, though he’s also trying too hard to be an aggressive salesman. If you had to guess this kid just wants to sell his knives just to prove to others he can sell things. Think lemonade stand type of business.

Another thing your perception roll can discern is the faint burn scars on his hands. If you had to guess, it’s possible due to the rather low quality of these knives, this boy is not only trying to sell you these knives, but he might have made them himself. 

Interestingly enough, these aren’t merely straight razors; you noticed a bit of a spring jutting out from the handle, which can help serve to both lock the blade in place once fully extended, as well as make the blade come out a bit more easily. Whatever the science behind it, it’s evident that this kid is trying to sell you his knives. 1 Silver is a bit more expensive then a knife of such low quality would warrant (1 Silver is like 10 US dollars nowadays) but he worked hard on them.