You are right, this information is important...even critical!
Here is what Trulia says, "Trulia receives listing from ListHub, a third party listing provider. As part of Trulia's syndication agreement with ListHub, Trulia has agreed to limit data edits on core fields (e.g. price and status) specified by ListHub.'
What this means is real estate agents are NOT RESPONSIBLE for the data appearing on Trulia.
Furthermore, those agents who recognize an error such as incorrect SF or # of rooms can not correct this data.
A recent report revealed that 30% of homes listed for sale on real estate aggregate websites such as Zillow and Trulia are actually NOT FOR SALE. The study further points out that homes appearing on these websites appear 7 days after they first appear in the local MLS.
I would think a serious buyer would want to use resources that give them a chance to win, not have their time wasted chasing the illusion of homes for sale and vapors of homes sold long ago. Contact a real estate professional in the area in which you have interest and have them enroll you on their MLS search program.
But, only do so if you are a serious buyer.
The service is FREE.