Two ESXi Hosts with all Live Servers

I  have a requirement to simulate an Enterprise level network as far  as  possible, with two ESXi5 Hosts & on those I want to install all  OS  like Linux(CentOS, Debian), UNIX(Solaris, FreeBSD) &  Windows(server  2003, server2008), integrating all those. And on those  OS i want to  implement all servers & applications as real time  environment, like  Mail server, FTP server, web server, LDAP server,  RADIUS server, DHCP,  DNS, AD server, Exchange server, MySQL, SAP etc. I  want to make it  heterogeneous network. And i want to implement all the  functionality as  far as possible like on ESXi5(FT, Migration, Load  Balancing, Clustering,  DirectPath I/O etc), on Linux(RADIUS, LDAP,  Mail, web, FTP, DNS, etc),  on Windows(AD, Exchange, etc) with all  server replications. And it  should be accessable to the public world.

So which storage solution should i go for?

I need the cheapest one.

What are all the basic & cheap models you have can onyone tell me?

thanks