Perhaps best product is one that has recurring monthly fees. This is known as residual income, and is best income to make, because you make one sale but are paid month after month.

Would you rather make one sale for a one-time $65, or one sale for a monthly subscription at $10 per month? I would rather have monthly subscription, because after seventh month I will have made more than $65 from first sale, and money will keep coming! It is possible that you can still be making money three years down road from one sale.

Here is another example to show you power of residual income: You work everyday for a company. Your paycheck is dependent upon your working. If you don't work on a given day and you are paid hourly, you will not be paid for that day. If your job is to make widgets on an assembly line, you must make those widgets to get paid.

But what if you were one who patented widget? Then you would receive income over and over again any time someone made or bought one of your widgets. You don’t have to make widget anymore, but you get paid every time someone buys a widget! This is residual income: it is income that you make over and over again from working one time. There are many great affiliate programs that you can market that can bring you residual income. You can also start your own subscription or membership website.

A related concept to residual income is leveraged income. Leveraged income is similar in that it can be residual. More importantly, leveraged income is money that you make from other people's efforts!