Because of the many scams and rehashed products, you need to be careful to purchase internet products.Many of the empty promises on the product sales pages are there to make you purchase their worthless products. Separate what works and what are a complete waste of money.
If you want to make real money online fast, then you have to go the route of arbitraging. Find sellers of digital services and locate buyers willing to pay higher prices for them. This is legal and legit. You act as the middleman, getting paid for it. Yes, it involves a bit of offline effort but its one of the fastest way.
From the service you offer, it need not be a one time sale. You can upsell and build a real relationship with your customers for repeated orders online so you can start building the foundation of your online business. Make enough of such relationships and you will have residual income online.