Farmer inherited a scarlet dyeing business at Worship Street, Finsbury which remained there under his name from about 1790 until 1817. On 16 Dec. 1793 he wrote to Pitt complaining that the indemnity granted to captured French territories in respect of their debts put him out of pocket and many West India planters at a disadvantage. On 2 Dec. 1795 he signed the London merchants’ loyal address. He invested in Surrey property at Woodmansterne, West Wickham, Little Pendrill and at Nonsuch, acquired in 1799, where he got Wyatville to build him a mansion (1802-6). He also had a seat in Huntingdonshire and property in Suffolk, Cambridge and the Isle of Ely. He was residuary legatee of his elder brother William Gamul Farmer, chief at Surat in the East India Company service, in 1798, and an East India Company stockholder by 1806.
As a badge of his prosperity, Farmer purchased a seat in Parliament from Lord Sandwich, who needed the money for his son’s county election campaign, in 1807. The sum of £4,000 was quoted.
Farmer, who retired in 1818, outlived his son, dying 14 May 1839 in his 92nd year.
