Regarding the transfer of a local photography collection--if your
    donor is willing, you can have a contract drawn up (with the help
    of an attorney) where a certain percentage of the collection is
    transfered each year to the Museum.  For example, each year 10% of
    the collection could transfer.  Such an agreement is often very
    appealing to a donor as they can take a tax deduction over a long
    period of time.  The contract could also include a provision for
    the entire collection to transfer should the donor pass away.

    Regarding valuation, I would recommend that you contact the
    director of your state archives for assistance.  Photos often fall
    under the title of archives--a difficult thing to value.

    Good luck--sounds like a wonderful opportunity!

    John Handley
    San Francisco