Add Leverage (Mortgage) and you greatly increase the ROI especially from the perspective of using Rents (other peoples money) to pay down the mortgage and increase your equity in the property over time. At this point then yes price appreciation is secondary bonus and we have an arguement of how and why Real Estate can be better than Growth Stocks in some scenarios and for some investors.

What are your thoughts on an Immediate Annuity as a passive income vehicle? I suppose it’s not a great investment since you never get your principal back, but the risk is zero and the cash flow is fairly good, approaching 6% currently. And, since you are guaranteed payments for life, you may not care that you never see your principal again anyway since you’ll be dead!
Coming from traditional employee positions, we are most familiar with linear income. If you work 40 hours per week, you get paid for 40 hours per week. And if you aren’t working, you aren’t getting paid. With residual income, you may put in a lot of unpaid hours upfront but then reap the rewards for months or years down the road. When done correctly, residual income can generate far more money than what it would if you were exchanging your time for an hourly wage.
Develop a website to purchase and then sell services, such as content articles or purchasing a product at a low price and then reselling it.  Another option is to sell the web design service. Sign a contract with an expert and sell the service to others. This type of business is low-risk and has virtually no start up costs. Sites such as eBay or offer products that can be purchased at a very low cost and then resold to gain a profit.
Investing is arguably the easiest way to make passive income.  The problem is most investments sound good in theory but don’t work out so well in practice.  And if you don’t have much experience or access to capital, let alone the time to work it all out, it can seem more or less impossible.  However, there is one smart way to invest that just might work.  Continue reading >
The return on investment of a specific department within a company can be calculated by dividing the departmental net profits by the costs generated by that department. For example, if the sales department generates $500,000 in revenue and carries $400,000 in costs, its net profits are $100,000. The return on investment can be calculated by dividing the $100,000 in departmental profits by the $400,000 in departmental costs, which gives an ROI of 25 percent.
When most hear the term residual income, they think of excess cash or disposable income. Although that definition is correct in the scope of personal finance, in terms of equity valuation residual income is the income generated by a firm after accounting for the true cost of its capital. You might be asking, "but don't companies already account for their cost of capital in their interest expense?" Yes and no. Interest expense on the income statement only accounts for a firm's cost of its debt, ignoring its cost of equity, such as dividends payouts and other equity costs. Looking at the cost of equity another way, think of it as the shareholders' opportunity cost, or the required rate of return. The residual income model attempts to adjust a firm's future earnings estimates, to compensate for the equity cost and place a more accurate value to a firm. Although the return to equity holders is not a legal requirement like the return to bondholders, in order to attract investors firms must compensate them for the investment risk exposure.
Now that you’ve chosen your market, find a way to start sharing your message, whether it’s a blog or podcast or Youtube channel, or whatever platform makes the most sense for your target market. Flynn says this is where you’ll start to build a fan base — and collect subscriber emails. You don’t need to get the whole world to follow you to make this work out financially. Wired cofounder Kevin Kelly wrote an article about 1,000 True Fans, which basically says that if you have 1,000 people paying you $100 a year, that’s a $100,000 a year. “You don’t need to serve everybody,”  says Flynn.
Many people talk about passive income and create the impression that you never have to do anything to keep that income going. The truth is that you will normally have to keep your eye on things if you want it to run smoothly. For example Richard Branson doesn’t run any of the 400+ companies he started but he goes over the numbers each day to make sure they’re performing well and calls the CEO if there are any problems.