I've always said, it feels like something as subjective as fair market value is an absolutely crazy thing to try to assess.
If Man City shirts are worth £60m, who is to say if ours are worth £60, 50 or 40? Makes no sense.
You could say "Hmm, that looks a bit expensive" but I don't feel like you can say it's unfair with enough certainty to fine people and dock them points.