Updated: Feb 8
These do not account for the condition, quality of materials, layout and other factors you cannot describe with an algorithm.
Although every area is different, most of these estimates are not near the final sold price for most homes in the East Bay. They do not account for the most important factor in buying a home, its condition.
The most information that I get from these estimates as a realtor is the amount of online interest other buyers are showing in a home since the estimates can change with consumer interactions.
Your representation matters greatly here.
Insight that only an experienced and hard working agent will provide is what other pending homes are in contract for. These are the future sold numbers that appraisers will use to judge the next set of homes that they need to appraise, possibly yours since these are likely closing before yours does.
These numbers are not public and not every agent will share what their clients are in contract for. However, if your agent has gained the professional trust of their peers and is pleasantly persistent they'll be able to at least get a solid idea of where it will land.