A reason for why a Seller would not want a buyer to know that their home is in contract escapes me. Typically, Sellers are pleased when they know unfamiliar people will not be walking through their home at all hours of the day.
If you do not trust the Seller to provide accurate information as far a status you can do any of the following:
1) Call the Listing Agent and ask for status.
2) Provide the property address to one of the Agents responding to your question so they can check.
3) Identify your own RealtorÂ® and have them check for you.
I would agree if you are buying a home you should find your own RealtorÂ®. In regards to finding this individual, the following sites, as well as a review of their Trulia profile/answers will give you good insight into the depth of knowledge and experience of each individual.
Note that DRE licensees are NOT bound to a Code of Ethics; only RealtorsÂ® take that oath, which can be viewed here: http://docs.Steven-Anthony.com/RealtorCOE.pdf
You can check to make sure an Agent is a RealtorÂ® by going here: http://www.realtor.org/rofindrealtor.nsf/pages/FS_FREALTOR?O
You can check the status of a DRE Licensee and their Broker (and past violations) here: http://www2.dre.ca.gov/PublicASP/pplinfo.asp
You can check for Desist and Refrain Orders, and Unlicensed Activities here:
Finally, I would encourage you to NOT enter into a Dual Agency (using the Sellerâ€™s Agent). Hereâ€™s why: http://www.trulia.com/voices/Home_Buying/Why_should_I_NOT_us