I serve as a curatorial consultant to small museums, having been engaged in the museum profession for more than 20 years. One way you might proceed to associate dolls, boxes, stands, and doll clothing items that belong together (this works for farm animals and boxes, tractors and boxes, anything and its accessory items) is to assign a single object number to the primary object in the grouping (for me, that would be the doll, animal, tractor, etc.) and then use a decimal and alphabetical approach to associate all related or accessory items to the primary item. For example: If the accession of the doll, box, doll stand, and doll dress were the second accession made in 2012 (and the numbering system incorporates the accession year as the first unit) consider numbering the doll as 2012.2.1a (or 2012.2.1.a) and the doll box as 2012.2.1b, doll stand as 2012.2.1c etc.
I’m less concerned with retaining the items’ market values as these objects have, as you say, been accessioned into a cultural heritage agency collection (museum, historical society.) Therefore unless one considers the collections fair game for generating revenue through sales (one hopes not!!) retaining market value seems far less important than retaining the primary documents’ association in the collections records, and by systematic and appropriate numbering of all items with primary relationships to one another. I suggest therefore that permanent or penciled object numbers be applied directly to all objects as soon following accession as is possible, in an unobtrusive and field-standard, best-practices manner. I’d be pleased to discuss this further with anyone – Patricia Keller patricia.keller at berrettstudio dot com