5-user License Pack including Microsoft RDS CALs (Windows Server 2008 R2 64-bit) $1,245.00
I am considering a server to run a full copy of SQL Server.
There are free-ware Citrix alternatives (linux usually) since Microsoft is considered to be anti-small business due to its licensing cost.
This has made the Citrix and freeware Retmote Terminal popular.
Citrix 5-user License Pack including Microsoft RDS CALs (Windows Server 2008 R2 64-bit) $1,250 USD
Looking at a licensed copy of Windows Server ($400 usd) or a 5 CAL Windows Server ($800) - this doesn't seem out of line.
Citrix is supposed to have a new small-business interface for managing the Citrix in a small business.
The Client can run Access or other windows products on any platform (apple, linux, android, ...) and run it securely remotely outside the LAN.
The secured remote aspect rather than a semi-cloud share on my home router is becoming more interesting by the month.
I am still evaluating BizSpark - the MSDN for small business. It is cheap for about 3 years. Don't know yet if it supports all of my needs (SQL Server, Development software, MS Office, ...)
Realize you just have a "server" and are not asking about multi-users directly.
I have used a server as a workstation. It pretty much will work for you. You might use around $8.00 to $20.00 USD a month more of electricty?