I know of a great company that does payroll management for consulting and temporary agencies. It is called Temp Financial Services (https://www.tfs-inc.com/hme.htm). They let you focus on your core business,. That is, acquiring clients, keeping clients happy, and recruiting. Temp Financial Services does some of your non-core, yet necesssary work like sending out payroll enrollment papers to your contractor, collecting weekly time sheets, processing payroll, invoicing your client, and monitor collections.