SharePoint 2013 on Azure

Hello,

We are looking to setup SharePoint 2013 in the cloud. We have Microsoft Open Licensing program. Also MSDN subscription of Visual Studio Professional.

What I wanted to understand is,

1. How many servers would I need to set up SharePoint 2013 on Azure (simple single SP and single DB model)?

2. What are the costs and licensing models that I need to use or leverage thru the Open Licensing program and/or the MSDN to keep the costs low?

Really appreciate your help.

Thanks

soumya