When we talk of investment, so many people do that on Facebook. They buy Likes which Facebook users offer for free. Yes, businesses and bloggers pay Facebook for Likes. I have seen some casual Facebook users believing that content owners earn when their content is liked; and I can understand where the confusion comes from.
It is also possible for Page owners to earn from advertisers depending on the number of Likes a sponsored post receives. But that arrangement is between the page owner and an advertiser.
You can promote a Facebook page by running a Facebook promotion. I have run some successful promotions where I spend close to $0.01 per Page Like. And since my Facebook page reflect the niche I’m in, whenever I post on the page, I get about 30% reach. Yes, Facebook won’t show your posts to everyone that like your page, you have to put in more effort by boosting.
When you boost a Facebook post on your page, you pay Facebook to show the post to several people. That’s why you see many posts with the word “Sponsored” on your Facebook feed. You can pay as little as $0.01 for every engagement, if you target well.
The best method to target and convert both in boosting and Page promotion is to target about 3 states/cities in a country, then target about 2 interests, and make sure your ads show only on feed of desktop and mobile device. Please ignore the Right Hand Side (RHS) or Right Sidebar Ads.
When a promotion takes off initially, the cost could be high. Just give it a day or two to start getting lower. Make sure to have a budget though, to avoid spending all your savings on Facebook because they will bill your credit card directly.