Thanks for your comments mjh .
If fees were on sales only and fixed at, say, 5% then the "dent" would be the same whatever value you had sold [pro rata].
So your £2 sale would attract a 10p deduct and £5 would attract 25p.
If the fees were at 3% deductions would be less still.
Just on the point of listing fees - this is the primary reason why I do not sell on Ebay.
Chris L