This is a tricky question but we are going to take a crack at it.  First let’s talk about what you’re going to need to get started. 

Pre-requisites:

1)      .NET Framework version 2.0 and 3.0

2)      SQL Server 2000 or later

3)      Windows Server 2003 or later

Without these you cannot run SharePoint so if you do not already have them it is important to include them in your cost analysis.

After you have all the pre-requisites we can begin to tackle “how much does SharePoint cost”, to which the answer is somewhere between none and a lot – see, now we’re getting somewhere. 

You will have two primary costs when acquiring SharePoint.  How much you pay for the server and what you pay for the user CAL’s.  You can download Widows SharePoint Services (WSS) for free on the MS website ( http://technet.microsoft.com/en-us/windowsserver/sharepoint/bb400747.aspx) and it does not require user CAL’s (that’s the completely free option).   This might be a good fit for small organizations looking for basic collaborative or document sharing capability.

For larger organizations you will need to look at Microsoft SharePoint Server (MOSS)

1)      Office SharePoint Server2007                                                                    $4.424

2)      Office SharePoint Server 2007 for Search Standard                                   $8.213

3)      Office SharePoint Server for 2007 for Search Enterprise                           $57,670

For medium sized businesses MOSS Search Standard should get you the functionality you need on the server side.  For large enterprises you will probably be looking to run MOSS Search Enterprise.

Next up, Client Access licenses (CAL’s).   The Standard CAL is $94 and the Enterprise CAL is $75. The Enterprise CAL is added on top of the Standard CAL for additional functionality.  So one Enterprise CAL will run you $169.