A family battle over the value of a house in Lewes, East Sussex, is threatening to block sale of the property. Now the dispute is heading for the High Court. Brothers Graham and Christopher Chaplin want to sell their late mother's house for £230,000, but the other brother, John, argues that the property is worth £300,000. Potential buyers are threatening to pull out unless the dispute, in which John has threatened to take action to stop the sale, is resolved. In their claim, Graham and Christopher are seeking a court order allowing them to carry on with the sale and banning John from interfering with their efforts to sell. Their claim comes in the wake of the refusal by John to give an undertaking to let the sale go ahead.