The following info is based on an analysis of approx 1350 sales of mixed flyers (from different events and different organisations) going back to July 2003. The trends that emerge may be of interest to both buyers and sellers, although variations in individual sales and changes in prices over time makes it difficult to predict accurately the value of any particular collection.
The info has come from auctions and sales on eBay.co.uk. Where the reserve price has not been reached, the highest bid has been used. Many items receive no bids, and these are not included.
condition of flyers
Collections which are ungraded or are in good or very good condition are worth approx 25% less than collections which are excellent or mint (see grading system). So a collection in excellent or mint condition which would sell for £10.00 is likely to fetch about £7.50 if it is ungraded, or is in good or very good condition. (Using info from sales of collections of 3-99 flyers.)
Note - older flyers are more valuable, but are less likely to be mint.
Collections with no information about the individual flyers are worth approx 20% less than collections which list the event name and date for each flyer. So a collection which would sell for £10.00 when fully listed is likely to fetch about £8.00 when no details are given of individual flyers. (Using info from sales of collections of 10-20 flyers.)
Note - valuable flyers are more likely to be fully listed.
number of sales, prices and size of collection