In our area, there are companies that do the market research and provide the data on all local companies. But, to be honest, I am not sure that it means a whole lot to any single seller. So what if ABC realty closes more deals? The reason is because they probably have more agents. If Agent A sells more than agent B it could be because she doesn't work alone or that she's been in the business for long enough she doesn't have to keep beating down doors to find the next deal.
I guess I am trying to say that stats on any particular agent or agency do not necessarily reflect anything that should be important to you as a seller. And, if you ask me to provide back up for any argument - ANY argument... I can generally find stats to back it up - even if I don't beleive the argument myself.
It's very hard to compare apples to apples.
I also agree with the prior post. If you are concerned about your property not selling, in today's market price is the major factor. No one wants to hear that, not even me. I find myself justifying thoughts that my house is worth more than my neighbors... but the truth is that it is not.