Housebuilder Crest Nicholson has rebuffed a takeover bid from the privately owned Heron Corporation run by Gerald Ronson. Crest said Heron’s offer of 345p to 430p a share, which could value the housebuilder at up to £480 million, significantly undervalued the company. Crest have also refused to allow Heron access to its books saying it will only do this if …