listbuilding+content locking?

So im thinking of build a list through classified sites...

Find a popular product on cb then search for <product> "Pdf" in google

Lock the link

Post on classifieds like..

Hey i just get a download link for <product niche!!!>from my friend.
I wanted to share you cuz very rare such expensive so bestseller blabla.....
Since i cant post urls email me for the link.

Or sth like that.

Respond a personal email and thats all.

Ofc it is just the main idea, it can be improved with autoresponders, email forwarders, bots and proxies, followups etc.

I hope you get it.. So what do you think?

So what? nobody interested?

It probably would work, but idea needs to be tweaked and it's kinda hard to get pass classified spam detectors now.....