Billing system for hestiacp

I’m looking for an alternative to cpanel and whmcs
I want to build a billing system like Blesta or HostBilling. which is devoted to hestiacp as the control panel.So later everyone who wants to build a web hosting system for sale. they use hestiacp as their control panel. bundled with my billing system.all customers logged in and interacted using port 80/443 using the hestiacp api. is this allowed under license or I have to pay for something else?

Thanks

You’ll find all informations you need here:

Thanks @ScIT