Flavor Billing - How it works?
Create pre-defined VM sizes (flavors) and set hourly price for each of them.
i.e. 512 MB RAM, 1GB RAM, 2 GB RAM
Setup initial package cost, that will be added to client balance as credit for future usage.
I.e. $5 USD - enough for 1 month of 512MB VM use
After purchase HostBill will provision user account in OnApp, mostly unlimited. You can limit VM count, backup size etc.
Client creates and destroys VMs directly from HostBill client area.
Every hour HostBill updates account billing details with number of VMs created and their sizes
Invoice generated is funded from client credit, client can top-up his credit balance at any point