Complex sentence: The house was owned for many years by Sir John Guinness, a former diplomat who also helped found the National Heritage Memorial Fundwho sold it after the death of his wife in 2014 for £2.75m.
Split into simpler sentences: The house was owned for many years by Sir John Guinness, a former diplomat who also helped found the National Heritage Memorial Fund. He sold it after the death of his wife in 2014 for £2.75m.