Mark,
Just following on from your previous thread…… I have just bought another bike (alloy / carbon road bike, 700c wheels, very different to my Raven) and it is being sent to me by Parcelforce 48. In a box 1.50m long and under 20kg it cost £18.25 which included £150 compensation. So if you can get a cardboard bike box from your LBS and some old bubblewrap, sending your bike to it’s new owner means a little work but is surprisingly cheap.