There is a few good incentives to offer, what i offer is Tcredits and PSA's, this way they grow and can enjoy some Tcredits doing auctions or games. Like any good team you need to show that you are invested in them and will help them along the way. Another good incentive is one not supplied by you, express how gaining a Team Leader position each month benifits them greatly, average CSA's each month per share is $100 and you get this all just for growing your business!
