Well, it depends on the type of targeted email list. There are 2 types:
1. Optin tageted list - This is the list that the customers have subscribed to received offers from the owner of the list. Paying for this list yields good results because the list owner is the only one in control of it. From my experience, the price for to send an offer to a list of 6,000 subscribers is between $37 and $67 just to send an offer to the subscribers.
2. Scraped email list - This is a list of emails scraped from niche websites. The list is also targeted but email owners did not subscribe to receive offers from the person selling the list to you. If you send an offer to this list, you may end up receiving spam complaints instead of getting buyers. Also, the same list can be sold to thousands of other people and the email owners would have already been spammed to death. To get a good list of this nature, it should be one that has not been heavily used. The list is usually sold. The price for this one should not be more than $20. You can use it again and again. This is my own opinion because I have never bought such a list. Also, it depends on who is selling to you.
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