Flutterby™! : Carefully read the TOS...

Kevin Roose in NY Mag: Silicon Valley's contract worker problem:

At least one on-demand start-up, Handy.com, has a contingency plan for a possible change in the law. The company's terms of service states that "if Handy.com is found to be liable for any tax or withholding tax in connection with your use of Users' services, then you will immediately reimburse and pay to Handy.com an equivalent amount, including any interest or penalties thereon." In other words, if Handy.com is forced to reclassify its contract workers as employees, its customers – not the company itself – will be on the hook for any extra costs.