I am just a buyer as you are... and I've learn a lot on this forum... so I own Trulia my opinion if this can help others...
Any agent would give you a CMA (comprehensive market analysis) as they have access to the MLS database and is their responsibility to do so anyway. But you can also see what what sold around and for how much.
I had a classic agent before - he was trying to make me buy one of his listing so he'll be dual-agent and receive the entire commission 5% .
Now I prefer to stay in top of my searching, know what's around and use REDFIN website & agents to help me with CMA and everything, because they rcvd salaries (not commission only if they make me buy). Also, there is a refund I'll receive from REDFIN at closing because their commission is less and they refund their customers...