Ive tried this and to be honest its better to get middle/high end parts.why?instead of going to nas path u better off using esxi (as what im doing right now). Esxi on thumbdrive 16gb,2tb hd,quad core intel cpu,16gb ram. Heres my setup

VM's
1.pfsense
2.Linuxmint
3.windows 8.1
4.xpenology/owncloud

Media server is on windows 8.1 with OpenMediaServer (support on-the-fly transcoding). Nas is on xpenology with integrated owncloud.

But thats me. I dont care hoow big the whole thing is as long as it serve my needs. And still, i have 5 more sata ports if more storage is needed.