Let me talk about the most widespread things that almost every person with the internet connection already tried - earning money online. I've been doing this for almost 5 years now, mostly from curiosity whether is it possible to earn money fast as promised from some sites.
I believe most of you have come across to certain PTC (paid to click), MLM (multi level marketing), PTP (paid to promote) etc. sites that promise earnings for you on a very low rate. BUT, if you invest some money in it to buy referrals your potential earnings would increase dramatically.
There are really only few of the sites that can actually do what is promised and those are the sites that started with this idea. We can see trillions of copies of the original sites trying to do business with the same original idea, but their intention is far prom being honest. I have come across hundreds of scammers, promising whatever to attract customers and invest in their plans, but after a month or so, they magically disappear. I would like to post out to everyone that is trying to get into the net of scammers - DO NOT BE NAIVE! THERE IS NO SUCH THING AS EASY MONEY! The only money that is worth something is actually the money that you earn from hard work. Don't spend your low-budget on such scammers, since it is not worth of your time.
On the other hand let me introduce you to some basic rules you should stick to if you are interested in such sites - try them out as a free member, search for the sites on the google, check out the owner of the site (using whois checker), check out the registration date of the domain, check out for how long the domain is bought (the longer time, the better, since it shows some seriousness from the owner, if it is short time and if it is off course free domain, then just leave it alone), don't invest anything before you check the background of the site itself and reviews from the members that got paid, also check out minimum payout ratio and earnings per click if it is PTC (paid to click site), since this is one way to see whether the site can hold the number of members (check how many of them are free members and how many of them premium - do the math) and how much they offer per referrals (if it is high ratio it means it will disappear pretty fast) and anything you come across to use as checking the sites honesty to its users.
By my experience the sites that put in a lot of effort for visual attraction and good plans are pretty stable. Be aware of the google ads as well or any other ads on the site, since this is the point out that they are not exactly a professional team of site owners and are not enough financially stable to payout members when time comes. If they are serious, they have enough finances to run the site with members buying advertising packages and to pay the members that view them. Rented referrals that circle monthly are pretty good benefit for that kind of sites as well, since the money flows all the time and it is impossible for some people that collect thousands of free referrals to destroy the payouts of the sites, since the owner would be paying only to them and nothing would left for the rest (free members or minority that paid for some of the referrals).
If you find something interesting, after you thoroughly checked out the site and reviews of payouts, try to get some referrals (but don't be greedy and make multi accounts, since you will get banned no matter how much money you would invest in their plans and there would be no refund ever), or even try to rent some small amount of them and upgrade for a low price and see how it goes. It will take some time to get to the payout and if you manage to get it, hopefully more than you invested, don't get greedy again by putting in higher amount then you already have before. Take it slowly, and after some of the successful payouts, continue only on the profits you gained, since most of the site owners are just waiting for the members to get greedy and put 2, 3, 4 times as much as they gained from the site just to get thousands of dollars, but as I already stated - THERE IS NO EASY MONEY - and usually this is the break point where the owners suddenly disappear and leave members with nothing.
So, if you must, take it slow. This kind of earning on the internet is just a partial job, it should not be your full-time job, since it could hit you hard if you get to greedy.
Think through, decide wise and good luck.