I am a commercial broker in an active market. I was told CoStar was the gold standard for data. I have found out otherwise and encourage any potential users to investigate thoroughly. This includes those who are currently members and relying on CoStar's data. I know most brokers do not dig deep into CoStar's system to verify data by cross checking with reliable and factual data from governmental agencies such as appraiser, clerks and corporation databases. If you do so, you will be shocked at the incorrect data that brokers and investors assume is correct. From misplaced properties such as residential units being placed into commercial databases to incorrect ownership information to many numbers being incorrect, all I can say is BEWARE! W depend on correct data to give to investors and clients. Should you actually spend some time researching CoStar you will agree that many items are a great cause for concern.