Do you still "preview" houses?

The last time I previewed a house, it was for a client who lived out of town who wanted to know if it was worthwhile making an eight hour trip to see a condo near her daughter's college. That made sense. Of course, I try to make caravan, but other than that, I don't bother with "previews." An agent made an appointment to see one of my listings last Friday. Naturally the seller cleaned and tidied up. She cancelled. Today she rescheduled and I found out it was a preview. Hmmm. The tenant said the place was presentable. I'm going to go over to make the bed...but I wonder if it is worth it?