While this is not my listing, the diffaculty with information using the internet has been a problem for many agents and marketing companies.
Often times there may be several different websites with information about your listings. Some websites such as Trulia get thier information from the local Multiple Listing Service (MLS). If you change the listing on one web site then it updates itself by using the data in the MLS then it will change the data that you have to the MLS's data. Or it could be data from an agents personal website, Or other websites. Some websites update daily others weekly or ever so many days. So what has to take place is to locate the place where the feed is coming from and correct the information there.... more