First of all, I personally believe that unlimited things doesn't exists. Saying about normal reseller hosting plans and business, most important thing is that customer's should not know that you are a reseller, so might need to get private name servers for your website. Secondly, understand the requirements of customers and try to create your plans accordingly. Also, the best way to earn customers is to help other people.
Create mutiple packages and give clients multiple options to select a package according to their needs. Try to keep the prices affordable till for a couple of months till you get known in the industry. Offer them good services and Quality support so that they bring more clients to you and increase your Business.