Well if you will live in Surrey .. are you using a vpn perhaps? the Yosepower.de site also sells to the uk btw, Fwiw i got my kit inc battery from yosepower.co.uk and an extra sensor from the .de site later, Very happy with both purchases and service..Does £260 include delivery? The Yosepower.co.uk site isn't listing a 36V20Ah and the .com site says it can't deliver to my address near yours. Website glitch or favouritism?
Ebay shows 3.5kg for 20Ah vs Yose 5kg for 17.4Ah, and for 20Ah 4.2kg, not wildly different if ebay's wrong and it usually is.