[mrreality68]

I am not sure what the number is but at some point the % will be to high that either the bidder will not be willing to pay it and go elsewhere or do without that item or the consignor will find another format/platform to sell it as they are getting a smaller piece of the pie(except perhaps a small portion that can negotiate for top cards). Because if you are able to sell elsewhere and pocket more of the money (that you would have given up to the auction house then their services may not be worth it)

I prefer private sales and/or trades but auction houses for now still get the bulk of the business because they currently get the vast majority of cards most of us desire