domain name appraisal scam?

Recently I get this kind of emails from some guy(s) who says he is interested in my domains:


I need a proof that our price is fair. I hope you understand the
importance of this question.

Usually, people who are selling names or web sites, provide buyers with appraisals. This is a common practice and I'm not going to change this rule because it's the best way to protect an investment.

I heard many appraisal companies often made inaccurate appraisals. So I cannot accept appraisal from each and every site. I will only accept appraisals from independent appraisal companies I know and trust.

Reading responses from experienced sellers I was impressed by one
reply: "Many Internet users are not smart enough and popular domain brokers are using this fact to make money. They offer them cheap appraisal services. But if their customers would have something in their heads they'd understand experts could not make a professional research for $15-$20. These appraisals are made by machines. Easy money for such appraisers as http://www.Afternic.com and several other major brokers that offer cheap auto-generated appraisals. In my eyes, all services under $60-$65 are not manual and the results are generated by special scripts. I don't trust auto-generated appraisals."

The same is true for GoDaddy and SEDO. Their services are not manual.
They are just collecting money using their well-known names.

Thank you for understanding. I'm looking forward to do business with you.

He probably has some appraisal sites and wants me to appraise the domains there, then he will not gonna buy them anymore.
If he was such a big domain investor, he should know which domains to buy and which not, without any kind of appraisals.