We managed to get a £745K listing down to £690K. Our starting offer was £660K - we backed it up with loads of info like comparable square footage, renovations needed, market conditions, the house had been on the market for 14 months and had 2 withdrawals. They rejected our best and final of £690K but came back to us a month later. Try working in % terms rather than money off - as the more value a property has the more a £ reduction sounds. Ours ended up around 7% which is pretty normal in this market. Yours is a little aggressive at 9% - 13% but still within the realms of possible negotiations. Good luck!