On Comp USA, full WinXP Home is $199, so if that person charges $100 for the installation, i'd call that fair. On the Windows on a Mac website (search it on wikipedia, i don't remember the URL) it says that you should only install it if u have some technical know how. So if you're an average joe out there who finally wants a mac but still needs windows and u don't know enough to be able to put it on the mac, $100 isn't that bad for the security of knowing that you won't screw up the installation. Hoewever, I think if it is home edition, the price should be $849.
I realize that you can get a copy of Windows XP a lot cheaper by buying an OEM copy. BUT, if you want to buy a copy to install on the Mac and sell it, legally, I would think you would have to buy the full version (not upgrade) of Windows XP. (This is assuming you are talking about XP Pro). The cost of Windows XP Pro SP2 FULL Version is $299.99 from CompUSA. So I guess the extra $300 for the Mini is justified, or is it? It does not specify whether it is Home or Pro.
WinXP Pro from CompUSA
http://tinyurl.com/nc8u3
Also, for me personally I don't want to purchase a computer that someone has pre-loaded for me. I am very picky!
Mac Mini w/WinXP on eBay
http://tinyurl.com/q8e2q

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