In the world of Commercial Real Estate...literally everything you see or hear about in reference to properties...is a source of information that may be useful to our clients. There are some specific examples of sources, such as The Atlanta Business Chronicle (physical weekly edition and daily updates), The Saporta Report (online paper), Bisnow National (online paper on transactions), GlobeSt.com, plus many more plus...by far the most important one is CoStar.
CoStar is subscription service which provides people in the Commercial R.E. field with infomation (data) which is invaluable for our industry. They are a national firm, which collects monthly updates about every commercial property in the areas they cover. They do this by calling (yes, calling!) every property owner to verify current status of property...is it for lease or sale, is it occupied, how high are the ceilings...everything is asked and updated, every month!
Such a tool cannot be understated. For example...when I started in the business, I use to have to drive every area my client wanted to be in, and call (off the sign) to see if they have the right sized space for my client. Many hours spent calling and verifying, now can be done in a few minutes. Difference maker!
Though without all the other sources of information I wouldn't be able to give my clients the very best all-around information about the market, and what is going on...at that time.
Sometimes it is what you know, not just who you know!
BTW, I don't work for CoStar! I pay them monthly, too.