"A bookkeeper records the financial transactions of an organization and takes care of day-to-day functions such as recording sales and invoices, paying bills and processing payroll," Stephens said. "Accountants take the financial data and analyze it to help organizations make financial decisions."

Connect remotely to your client's computer to balance the books, just like if you worked on-site. Work through an online cloud-based bookkeeping software (such as QuickBooks Online or Xero) with your own secure login. Use the same desktop software you're used to, but accessed through a hosted virtual desktop.

A bookkeeping side hustle offers incredible flexibility. It allows you to balance work with personal life. It also opens opportunities to work with a wide range of clients from different locations.

The work requires attention to detail and a good method of keeping track of constantly fluctuating items, which leads most bookkeepers to adopt the double-entry method of accounting. Much of a bookkeeper's work involves not only the entering of information, but the review of information and the reconciling of accounts.