The official EULA isn't online yet.
I haven't done a clean install of W7 in a while, so I'm not sure what it says during the install. Pretty sure I remember seeing some sort of EULA though.
The other issue is that the person you're selling this to is going to need to buy a copy of W7 to use once it gets past the trial period (and starts shutting itself off automatically). Make sure they know this ahead of time.
Unless you want to support the machine every time they hit a snag, (W7 is still in testing after all), I wouldn't do it, but the choice is ultimately yours.