It may seem strange but consider this....
- There are a lot of real estate sites on the Internet. Some of them are biggies like Zill_w dot com and Trul_a dot com. These sites are often sited as the "recognized" expert or the quoted "proof" depending on the person using them. But the information, particularly real estate listings, is rarely current.
- There is a lot of information on the Internet but who can publish on the Internet? Anyone can publish anything to suit their purpose. There is no source to verify before the publish button is pressed.
- Data "scrapers" are only grabbing information without scrubbing it for accuracy. The joy of automation.
- A local knowledgeable real estate agent who has access to raw information who can screen it for what you are seeking whether homes for sale, sold properties, a market analysis or whatever purpose.