Let's say, for a minute, that you are interested in buying a rare collection of Mormon documents. How rare?
Well, let's just say it is a collection of all the papers of an early member of The Church of Jesus Christ of Latter-day Saints.
How early?
The LDS Church was organized in April 1830. This guy, Reynolds Cahoon, was baptized in Oct. 1830 and died in 1861. He followed the church from New York to Ohio to Missouri to Illinois to the Salt Lake Valley. He was well-known by early church leaders and even participated in plural marriage during Joseph Smith's lifetime.