I always compare my prices to those of the major dealers such as Pam West and Simon Narbeth. Pam West is the one is responsible for me developing an interest in banknotes when I came across ‘English Paper Money’. Brilliant book. I suggest when spending serious money to always look at the prices offered by these two dealers. Just now, Simon Narbeth has the £50 Polymer (AA01) at £125 which is very good value as on eBay the note is selling for £165 – £190 per note. I do try to keep my prices lower than the above dealers, but they have fantastic collections. Look at their two and three digit serial number prices – a really good guide.