We are currently in the process of opening a new accounting firm in the new year (actually moving from our previous location).

I am looking for a cheap/free solution to back up our files (small, text files couple of kb). I was impressed with FreeNas and Windows Backup but I found out that Windows Backup only saves for a maximum of 2 years.

The work machines will be running Windows 8 or Windows 7. There can be many work machines however we have only one to start with (ie, think of it as just one employee). I have an old core 2 duo with 2 gigs of ram that I can convert to a server if need be. I want the syncing to be done through LAN since the data is confidential and should never touch the outside world.

So ideally, I would like the following scenario:

• A skydrive/dropbox like service to sync my client files over work machines and a central server.
• The "server" part should store history of files (i don't know how this will be done since the file will have the same name?). This isn't really necessary, but I can see it become useful.
• I am not familiar with RAID, so does any software RAID solution exist? I will most likely be buying 2 hard drives.