Per-client pricing
Charging per client company ties vendor cost closely to firm revenue. Each client you add brings a known software cost, which is easy to pass on. The downside is that very small clients can become unprofitable if the per-client charge is high relative to your fee.
Per-client models often bundle the white-label features into that charge, so there may be no separate firm fee. Check whether branding, staff access and exports are included or sit behind extra plans. A low per-client figure can look different once those extras are added.