Pete, like any record, the price what they should be worth has no bearing on the price they fetch.
As I said - your prices are more than fair, I know cus I've had plenty of 45s of you that I would consider to be bargains....
Supply and demand is the name of the game of course, so although you consider it to be worth £25, you would buy it for £40 to sell for £50 to make a tenner.
That is a very fair and honourable profit margin ( too low for most business' if the truth be known)...but at the end of the day you have still paid £40 for a record you consider to be worth £25, so what is wrong with some-one who considers it to be worth £80 paying £100???
I presume you don't like to sell on ebay too much, but if you could sell it for over £100 on ebay, why sell for £50 on a list?
Only asking so don't get narky....