So you want to buy a photograph. Here's question 2 in the series of 5 posts on what to ask before buying a photograph.
Question 2. When was the print made?
Prints can be made years - sometimes decades - after an original negative was produced. These are called modern prints, and, in the case of them being produced by an artists's estate posthumously, estate prints. A vintage print is a work made within one or two years of the original negative, and is generally more valuable.