Hi Eric, great question and I'm glad you asked it before you go any further. You capture well the disjointed process of trying to work with individual listing agents - it is cumbersome and awkward. So no, I do not recommend you do that. Rather find yourself a great agent - full time, knows the market and inventory well, is responsive, works as you do, has the analytic skills to tap and put the substantial data to work to benefit you. Trulia is a great place to begin your search for agents - go to the "find a pro" section and put in your town/zip and you'll see a list of active agents to consider - review their profiles, read their contributionsa and testimonials and don't hesitate to ask to speak directly with references.
I find that the home search comes into focus over time - and the agent can be of great value as your advisor but only if she is guiding your search overall. You do not achieve this is you work with many agents. Another disadvantage of working with many agents is that it diminishes the effort any one agent will put in to the relationship. Find yourslef a great agent and reward her with your loyalty.
Incidentally, I rarely ask a buyer to sign an exclusive buyer agreement until I have earned their trust and loyalty - and when I have, there hardly seems a reason to ask. I look at those agreements as a tangible sign of the "gentleman's agreement" we have in place.
Good luck to you,
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