Have you ever sold a home to a buyer that was sight unseen? I have on several occasions. It can happen for a number of reasons. It might be because a buyer chooses to purchase new construction and the home isn't built yet (though they can usually see a model), or perhaps they are out of state and can't make the trip prior to their move. In any case, it happens.
It's helpful if you've previously had the chance to show them homes in person. Then you have a good feel about what matters to your client, and more about their personal tastes. I do ask them a lot of questions, and take a lot of photos to help with their decision. I also like to call them while I'm at the property. I think it's easier to relay a sense of the home that way.
Yesterday I got an e-mail from a client asking me to write an offer on a home they haven't seen. I'm going out now to go take a look at it in person. They have seen all the photos in Multiple Listing and like the home a lot. They feel it is reasonably priced. They want me to make sure there is no glaring problem with the property that is undetectable from the photos. Of course, I will also run comps to be able to have a discussion with them about price. Luckily, I was able to go out with this client a few months ago when they were in town, so I have a pretty good feel for what they like. And today I will take out my new Flip video camera and take some footage to send them.
So far, all of my buyers who didn't see their home until after they bought it, loved it!