If you're already the person clients call when their website breaks, reseller hosting is really just formalizing something you're probably half-doing already.
Instead of pointing a client toward a hosting company and hoping they figure out cPanel or Plesk on their own, you create their account yourself, set the limits, and stay the one point of contact for anything hosting-related — which also means hosting becomes a line on your invoice instead of a favor you do for free between projects.
Plesk specifically tends to suit teams already comfortable with its interface from client work, or anyone who'd rather hand a non-technical client a simpler panel than a denser account tree. The plans below start at 10 customer accounts and scale up from there, so it's realistic to start small and grow into a bigger tier as your client list does.