After some opposition from his father, he was allowed to accept of a commission offered to him by Lord Archibald Hamilton, in the 13th Regiment of Foot.
[5] He also obtained the badly worn original plate of Rembrandt's "Hundred Guilder Print" and reworked it.
[6] His main business however was as a picture dealer, acting as agent for the Earl of Bute[3] and Lord Liverpool among others.
[2] He was highly regarded as a conoisseur in his lifetime[2] although the admiration was not universal: John Thomas Smith said that Baillie "could not draw, nor had he an eye for effect", singling out for particular criticism his copy of Rembrandt's Three Trees, into which he introduced flashes of lightning.
[2] His works were published in two folio volumes by John Boydell, in 1792, under the title of A Series of 225 Prints and Etchings after Rembrandt, Teniers, G. Dou, Poussin, and others.