At Google we did a comparison of many, many "patent search" firms: giving them all the same task. Unfortunately I couldn't tell you the results even if I remembered them (which I don't). Most were garbage but a couple were spot-on.

It's more than $3,000; I can tell you that.

Secondly, it's detective work; you might get the answer right away, and you might spend days searching fruitlessly. Making a claim chart is what take the time: you have to hit every single element.