In our market (Portland, OR), not enough users implement the tools that could make CoStar so much better. For example, I specialize in medical but brokers and owners don't take the time to mark medical as an approved use in their buildings so I have to search much longer and cross-reference the data by contacting the brokers directly.
I find it really annoying that when I download documents CoStar doesn't use smart technology to automatically name my files. It is especially irritating since every piece of marketing we post to CoStar has a relevant file name yet when we download the same file we have to rename it.
One of our landlords requested we try VTS but we didn't continue because it was such a small portfolio it too more time to update the database than we wanted to spend
Since CoStar has linked with LoopNet we have had fewer bad data calls. By which I mean old data from LoopNet that was available to the general public is now more regularly updated through CoStar so we have less confusion with our clients.