Anyone who claims you can't cram a quart into a pint pot should visit the house owned by Iain and Rachel Boyle. It is only 6ft wide and 21ft from front to back. Yet in that tiny space is an entrance hall, kitchen and shower room on the ground floor, a first-floor living room and a bedroom in the eaves. Mr and Mrs Boyle believe that the former donkey-cart shed could be Britain's narrowest inhabited terrace home and have written to Guinness World Records to ask if they are right. The slender house, which is sandwiched between two unremarkable houses in the middle of a terrace, is 21ft deep and 6ft wide The couple, who run a publishing business, bought the building in the Hollingdean area of Brighton for £8,000 12 years ago. They spent another £15,000 turning it into a stylish pièd-a-terre and now rent it out. Owners Iain and Rachel Boyle, pictured with sons Joe and Charlie, believe it must be Britain's narrowest inhabited terraced home Mrs Boyle, 45, said: 'There was stil