When do we bring in another person to help us promote and book our music duo?

- We are Song of the Lamb, a husband and wife Christian music duo. www.songofthelamb.net- We travel 6 months of the year in Canada and the USA. - We now plan to spend 6 months of the year mainly booking but doing some local concerts. - We book concerts by phoning first (we use magic jack for low rates) and then follow up with an email. - We play mainly Catholic churches and schools but sometimes other Christian churches and schools. - Right now my wife Cyndie helps build the database and I do all the calling and emailing. - If we hire someone would we try to pay by commission or an hourly wage? - Is it best to find someone in our area whom we can meet personally? - I am able to get us bookings but it takes a lot of time and energy and I've been pondering the idea of leverage and if it would be a great help to have another person to do this task as well.