Can I Import my existing Book of Business?

Yes and Agents are doing every day!
Under both the Lead and Client Screens there is a link to Import Leads or Import Clients. The link directs the user to the Import Page which provides both import directions and a sample Excel File (.xls) to use. With Radius Custom Fields the sky is the limit to which existing data can be imported.

Hint: Create the Custom Fields First, then build out your Import XLS file around those fields for import