please is there anyone who can share experience with the way on how to install OpenNebula
so it can be used for KVM VPS (virtual private server) reselling?

So far i found the PHP module for WHMCS billing system that is using OpenNebula API:
There is also module for Blesta billing system:
https://marketplace.blesta.com/#/extensions/24-OpenNebula%20Provisioning%20Module%20For%20Blesta% 20