I contacted a facebook group admin, which is having 80k members and growing every day in a targeted niche. The group is very active, sometimes it get 1k+ like for an interesting image post. Most of the people are from USA (Black American Women) He is ready to pin my post for 7 days for $50. I am thinking about promoting a CB product there but i am not sure if this kind of advertising will work. $50 is still a big deal for me because i have never invested that much in one time before. So, i need you guy's suggestion before taking this risk.