(help monetization)Want to build a directory

I want to build a directory about profesionals:

Issues:

-Which would be the best option the call them and invest monthly fees on the project so the would like to join (they will be show on the site so people who is searching that kind of profesionals would contact them).

-How much should be they paying for a service like this? If this is the way to monetize it.

Recomendations? suggestions...

Think that this post goes in the MAKING MONEY section if someone can PM a moderator to move it will be great. Sry about the miss placed of the thread. If you want u can delete this post after you move the thread. Thx

You would list all types of professionals in that directory?

Nope just 1 type of professional

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