As I suggested with my multiple questions, this is a very broad topic. Let me give you some tips, that for sure won't answer everything.
If we consider AWS, there are white papers and documents that you may reffer to on how we can work with Amazon's cloud. Anyway they are improving their offering every day, so I suggest contacting them. Please remember that they are tecnology partners.
I know that they can offer from a pure hosting to a virtual server inside your LAN.
We have multiple OEM partners with a SaaS solution with multitenancy. I may reffer to our website and QlikMarket.
Regarding the "Private Cloud", there is a partner offering a managed service to install QV in a hosting/housing mode. www.biycloud.com As they are smaller than AWS I guess that they may offer you a more ad hoc solution. They work mainly with QlikView so they can give you advise on how you have to configure the service.
Sorry for the broad answer, but it was a broad question.