It could be that the new owners have done some renovations and added more bedrooms/baths to the home.
It could be that the person inputting the info wasn't correct in doing so, etc..
Really the best way to gain info on a home is through a licensed realtor in the area of the home. We pay good money for access to our MLS database, which is the most current and accurate database there is. It can't be accessed unless you're a licensed realtor or member of the board.
Many agents will be glad to get you the info you need concerning this house, me included :-)...Please let me know if you'd like me to email you homes in and around the Beltsville area. 301-423-9200
Thanks for your question, it was a good one!