The only figures that count are the prices actually realised for comparable pieces in comparable condition, not the often far higher sums asked in current listings. Anyone who takes such fantasy prices as his basis will overvalue his collection every time. Condition, the completeness of box and papers, and the question of whether a pen has been used, make a considerable difference. For individual high-value or hard-to-place pens there are valuations to be had for a fee, for instance from the circle around the standard work “Collectible Stars”; they are only worth it on correspondingly expensive pieces.
When it comes to selling, convenience stands against proceeds. Dealers take pens on commission or buy them outright and keep a share for doing so, which as at 2010 was around 25 to 50 per cent of the value, at times more. In return, the photographing, describing and handling fall away, and good contacts can speed a sale up. Selling yourself, through an auction platform or at collectors' fairs, brings in more but means documenting every piece properly. Without telling photographs, an accurate description of condition and an idea of the price, no buyer will come forward, and if one does, then only with a hefty discount for the risk.