That's high, I've seen partially trained (young) gun dog's (cocker spaniels) go for £2-3k. When their fully trained, the sale is normally by private agreement. A quick and easy way to tell an intelligent dog to determine if it is worth training. Stand in the garden and point at something in the distance with your arm outstretched. A dog with 'training potential' will look where you are pointing. The rest will just look at your arm.