Rental properties are defined as passive income with a couple of exceptions. If you’re a real estate professional, any rental income you’re making counts as active income. If you’re "self-renting," meaning that you own a space and are renting it out to a corporation or partnership where you conduct business, that does not constitute passive income unless that lease had been signed before 1988, in which case you’ve been grandfathered into having that income being defined as passive. According to the IRS, "it does not matter whether or not the use is under a lease, a service contract, or some other arrangement."
It was easier recouping the lost $60,000 in rental-property income than I expected. For so long, my primary mindset for passive income was rental income. Having $815,000 less mortgage debt but still generating roughly the same amount of passive income with a much larger cash balance feels great. Further, my passive-income portfolio got even more passive, which is good as a stay-at-home dad to a newborn.
2. Real Estate: Real estate is #2 for one simple reason, leverage – using smart debt and other people’s money. When looking at real estate rents and the potential for income real estate provides, it is the trifecta of residual income. First, a home or rental property can appreciate, so capital appreciation is the first long-term benefit of owning a home. Second, rent. Other people are paying the mortgage, insurance, property taxes and maintenance while you own that piece of real estate. Third, tax protection. Rental income is taxed at a lower rate than ordinary income and you can depreciate real estate by taking a paper deduction on your annual tax return not to mention expensing the cost of mileage, mortgage interest, and updates to the property. Rentals done right can generate almost double what the stock market can in dividends and interest. The fourth and maybe most hidden, but important benefit is that over time rent’s rise, protecting your cash-flow against inflation, while your mortgage interest can be at a fixed rate potentially.
One aspect you might want to add to your scoring is “inflation protection”. At one end, bonds and CDs generally pay a fixed nominal coupon that doesn’t rise with inflation. Stock dividends and Real estate rents (and underlying property value) tend to. Not reallly sure how P2P lending ranks- though I suppose the timeframes are fairly short (1 year or less?) and therefore the interest you receive takes into account the current risk free rate + a premium for your risk. Now that I think about it, P2P lending probably deserves a lower score in the activity column than bonds too (since you probably need to make new loans more often).

Let’s say you just decided to sign up for the Chase Sapphire Preferred® card. Once you had the card in hand, you could begin using it for purchases and earning cash back for every swipe. For every dollar you spend on regular purchases, you’ll get 1 percent back in the form of rewards. For dining and travel purchases, on the other hand, you’ll score a smooth 2 percent back.

I agree mostly with the real estate advice. I’m looking for ways to take advantage of the condo I own to get up the rent from ~$0.90/ft to the $1.2-1.5/ft that seems more like the range in the same area. I’d have to put in a bit of capital (probably 10k on the low end for just the basics up to 40k if I wanted to remodel the kitchen and 2 bathrooms up to par with the area), so the return is likely there if those upgrades warrant $1.30/ft (given the unit is larger than most 2br/2ba in the area).
Residual income is calculated as net income less a charge for the cost of capital. The charge is known as the equity charge and is calculated as the value of equity capital multiplied by the cost of equity or the required rate of return on equity. Given the opportunity cost of equity, a company can have positive net income but negative residual income.