here's a link to the Big Mon model from the Northfield page:
http://www.northfieldinstruments.com/mandolins/big-mon
browse thru that and you can see the base price list of $4250, then for that mandolin in the classifieds it appears to have some extras of black top, violin neck, varnish finish(not sure if the base price includes varnish finish or not), deluxe headstock inlay, and probably some other items I've not noticed. So those extras add on to the base price.
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