Readers of Thoreau's Walden might be forgiven for thinking that his experiment in living was one of economic autarky. The way he describes things in the section on "Economy" certainly give that impression. For instance, after detailing his expenses, he states that "my whole income from the farm was $23.44".
Yet in a journal entry from October 4, 1857, he notes that "while I lived in the woods I did various jobs about the town - some fence-building, painting, gardening, carpentering, etc., etc." He then describes some of these odd jobs and says that he charged only a dollar a day (earning at least $9 just from the two masonry and fence-building jobs he happens to mention in this journal entry - apparently there many more). Thus Thoreau was perhaps more of a freelancer than the hermit he's commonly made out to be, even during the mere two years that he lived at Walden Pond in relative isolation.