I have never heard of an arrangement like this before.  I think
    some issues to address are (1) would your museum purcahse
    the art work if it were for sale (because if you must meet this
    clause, that is exactly what you will be doing) and (2) I would
    try instead to strike a deal where each year the museum obtains a
    percentage of the ownership title of the work and avoid all
    together the issue of market vale.  The ideal (since they won't
    outright give it to you) is to own free and clear as much of the
    work as possible, gaining complete title to the work within a
    specific time period, let's say, over the next five years.  This
    type of arrangement is becoming more and more common.

    The arrangement as stated, does not appear to leave your museum
    much recourse, and also leaves you prey to someone else's poor
    money management.

    Good luck.

    John Handley
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