BMT:
As to the 2nd part of your post: I agree and disagree at the same time . . .
First, as a serious collector of 40 years, I can attest that it's very, very difficult for any serious collector to acquire and put together a comprehensive collection of something, acquiring one here and two there, until one has amassed a major collection, only to sell it off piece-meal when you feel your time is through as a serious collector.
It goes against all the grain in your body to break up what it's taken you all those years to assemble!
Second, DO NOT ASSUME that once a collection is left to an organization such as a library, etc. that the collection will be:
1. Safe for posterity
2. Available to interested parties.
Museums and libraries have been famous over the years for selling off and/or trading donated items that were bequeathed to those organizations in good faith by the collector. For example, if they have a collection of LIRR glass plate negatives from the 1880s and have the opportunity to trade them for some Tiffany lampshades, etc., the glass plates go bye-bye.
It's no secret.
Look at what the libraries, etc. charge an intrested person for a blow-up of one of their donated negatives. I believe the Brooklyn Public Library, which has all of George Brainerd's 1870s-era negatives charges $20.00 a hit for a photo. And the darkroom "tech" doesn't care too much about his/her printing quality either.
Then there's the Chaney LIRR collection at the Smithsonian. See how available photos are from that collection and the price.
A serious collector is torn between keeping the collection together (which limits a buyer for the collection as it becomes huge) and making some easy money from it (as he/she has invested LOTS of money into it over the years and would like something back.) by selling it piece-meal on e-bay, etc.
It's a hard, gut-wrenching choice.
Dave Keller