If you haven't read Jennifer Allens post : My-Four-Month-Anniversary you really should. In this post Jennifer gives 8 powerful points, on what does and doesn't work in the real estate biz.
"Point 6. Don't delete someone from your database because you never hear from them and think they don't like you. They probably like you fine; they're just busy living their own lives." 
I completely agree. While my business is nothing to emulate I would tell anyone just getting into the business don't delete. It's easy to say "well, I'll never hear from that person again" it may not be true. This is especially true when you are new and your confidence isn't what it should be. I'm continuously amazed at how many people I will hear from that I'm sure have dropped off the planet.
Example 1- a local agent. I've e-mailed him, dropped by his office, left notes and no communication back. Last week I finally got a hold of him and asked him why I hadn't heard from him in literally years. "I get all your e-mails, didn't know you needed my attention." OK, not the response I wanted but its good to know he does get my e-mails.
Example 2 - a woman that was part of a past networking group. Same thing, she is getting my e-mails and called to see a property I sent out via e-mail to hundreds of people.
Example 3 - I got a call from a potential listing from 2 ½ years ago. Now he wants to list with me! I still have his info.
Example 4 - Recently I went thru old files in the office. I took EVERY e-mail I could find and added it to my e-mail list. Surprise, of the hundreds I added a few are still looking for property. Time well spent!
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