Keller's "30:10:3:1 Lead Generation Ratio": how do you do it?

[John Blythe]

Hi all In Keller's "Millionaire REI" he mentions the 30:10:3:1 lead gen ratio on page 216. It makes sense and sounds great. I'm curious, though, what you think the bridge is in between 30 and 10. He says the 30 meet his criterion but that the 10 "warranted serious investigation." What makes it so? Basic analysis of numbers? More info found via a walk through? Something else? Ditto between 10 and 3 (only 3 are worth making an offer on). The 30 are assembled by the criterion and the 1 deal is sifted from 3 by the terms, so I'm wanting to know what mechanisms you think he is assuming for the other two steps and/or what *you* use in those steps to whittle down. Thanks for any input!