Since you say the provider has no EMR/PM in place, one option could having the provider sign up for Practice Fusion(it is free) for the EMR, and that is also where the provider would generate superbills, and then having the provider pay for one of the cloud based PM systems that Practice Fusion integrates with, such as Kareo or NueMD. Kareo is better than NueMd, but NueMD is cheaper, I think.
You get what you pay for, and I don't know that I would go completely "free" on this if I was the provider. You, as the outsourced biller, should really not be eating the cost on any of this, also.