If someone does not use ClickHome but you want to apply their name to a job for the sales person position and do not want them to take a licence.

Navigate to the the user details screen and uncheck the "Internal User" tick box and apply the security role of "Sales Person - Addon". If this security role is applied without unchecking the internal user tick box then it will incur a Limited Access license

Once this is done you will be able to appoint the user as a Sales Person on a job in the management tab: