Outlook Web Apps Server for Lync 2013

Hello All..........I have a Standard deployment of Lync 2013 (FE, E and RP).  Now, I am looking to add Outlook Web Apps Server. So, have following questions in mind?

1.  Is Outlook Web Apps Server free of cost?  OR one has to download through Partner Portal?

2.  Can Evaluation version of Outlook Web Apps Server be downloaded from TechNet Evaluation Centre and is it possible to activate the Evaluation to RTM?

3.  What should be minimum hardware configuration?  CPU, Memory and Disk?

4.  Any step by step guide would be appreciated.

Thanks in advance.