Maybe it was entered incorrectly by your agent?? This site just pulls listings from various sources, such as local MLSs. It's best to go to the source of the bad info. In this case, I'm guessing your agent. Also, keep in mind that different MLSs report SF differently. Some only show "above ground" SF, while others will show total SF, counting an unfinished basement. This could also be the reason for the discrepancy. Again, I'd talk to your Realtor and see what the issue is.