Hello and welcome! My name is Doris.I have been an antiques collector, dealer and appraiser for over 56 years.I will be pleased to help you.
You may have already seen this reference; but just in case you have not, I am including it here.
Your set of cards and viewer would have an estimated retail value of $2000-2300 assuming good condition but for a needed repair to the viewer. Sales value also depends on location.
Online auctions like eBay generally bring wholesale selling prices.
If you would like to sell close to estimated retail, some ideas are:
The internet has your largest audience of buyers. Place small ads on these sites or set up your own small store on these sites.
Etsy.com - small fees - 20 cents to list plus 3.5% final price.Artfire.comBonanza.comAmazon Marketplace: http://services.amazon.com/content/sell-on-amazon.htm/ref=footer_soa?ld=AZFSSOA
Or your nearest CraigsList.com where you can list items for free.
These sites are excellent and more upscale but fees are higher. I only recommend them if you have several items to sell.GoAntiques.comRubylane.comTias.comcyberattic.comtrocadero.com
In general, a private seller to a dealer or at auction can expect 30-60% of estimated retail value.
Insurance replacement values are usually about 10% more than retail values.
I hope I have helped you.
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