There are many residual income business opportunities. It's often hard to find a good one.
Checklist for evaluating the various residual income business opportunities
In general, holding stock, dealing with deliveries and returns, is a nightmare and best avoided. No matter how wonderful your product, people will change their minds, send things back, and repeat business is not guaranteed.
The best product is what is called a pre-sold consumable; these are products your customer uses regularly, and is billed for monthly or quarterly. So long as your product is well priced and properly supported by the company, you will find the highest levels of residual income from these products. They have the added advantage that you never have to deliver electricity in the rain, or pay a refund for unwanted water and then wait for the company to reimburse you.
Residual Income Business Opportunities
Residual Income Business Opportunity
High Demand Product Residual Income