 He spent over £30,000 purchasing the estates of the Island of Danna, Inverneill, Knap, Taynish, and Ulva.He also purchased the houses of Inverkeithing and Queensferry.In 1774, after an unusually bitter electoral battle with Colonel James Masterton (1715–1777), of Newton, Colonel Archibald Campbell (now styled 'of Inverneill') became the Member of Parliament for the Stirling Burghs, aided by his guardian, Viscount Melville.