In 1792, he built his country seat, Beaver Hall, which was one of the early estates of the Golden Square Mile. The wife of Lieutenant Governor Sir John Graves Simcoe observed in her diary that Mrs Frobisher, "lived in great style and comfort, and had an excllent garden". Since retiring from the fur trade in 1798, the sociable Mr Frobisher had enjoyed the good life and developed a passion for sumptuous dining to the extent that he kept a diary specifically for recording his dinner parties. His dining room comfortably sat forty guests, and even though he was not in the best of health from 1806, he continued to dine out or entertain in his home every night of the week. He was secretary and chairman of the Beaver Club from 1807 until his death, and they frequently met at Frobisher's home. Frobisher died at Beaver Hall in 1810, and his home succumbed to fire in 1847. In 1779, at the Anglican service in Montreal, Frobisher married a girl twenty years his junior. She was Charlotte Jobert (1761-1816), daughter of surgeon Jean-Baptiste Jobert and Charlotte Larchevêque. Her aunt, Marguerite Larchevêque (1749-1798), was married to Charles Chaboillez, one of the most influential French Canadian fur traders, who with Frobisher and his brother was one of the founding members of the Beaver Club. They were the parents of fifteen children, but only three lived to adulthood and married:   The Frobisher brothers gave their name to the Baffin Island community called Frobisher Bay, which in 1987 was renamed Iqaluit, and is now the capital city of Nunavut territory. The body of water on which sits Iqaluit is still known as Frobisher Bay. There still exists a Frobisher street in Montreal. Beaver Hall Hill is a street which follows the beginning of the path up Rue Belmont to the location of Frobisher's country retreat.