The brothers worked well together: Benjamin's talents laid in management and he concentrated on running the business with London from Montreal.

When Benjamin died unexpectedly in 1787, as Joseph knew very little at that stage of the management side of the business (and Thomas nothing at all), the two brothers went into partnership with Simon McTavish; both firms being part of the North West Company.

Frobisher was part-owner of the Batiscan Iron Works and, with his partners, purchased the seigneury of Champlain, located on the north shore of St. Lawrence River, near present-day Trois-Rivières.

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 excellent garden".

[4] 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.

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.

Beaver Hall Hill is a street which follows the beginning of the path up Rue Belmont to the location of Frobisher's country retreat.