Project linked: The model depends on the client. Main options are:
Software included into the overall project costs (preferred)
"Pay-per-use" approach - e.g. based on
number of components (e.g. in slots: upto 50 components, 50 to 1,000 components, 1,000 to 10,000 components, more than 10,000 components...)
time in which the cloud can be used
number of users
Annual license + maintenence
JV-based models
Other, customized to user's needs ...