In January 2018, I missed my chance of raising the rent on my new incoming tenants because it didn't come to mind until very late in the interview process. I didn't write about my previous tenant's sudden decision to move out in December 2017 after 1.5 years, because they provided a relatively seamless transition by introducing their longtime friends to replace them. I didn't miss a month of rent and didn't have to do any marketing, so I felt I'd just keep the rent the same.
If you have an empty house or room you can rent it out on AIRBNB and OYO Rooms. Many travelers are looking to spend one night at a place. You can always rent out your empty house or room to them. All you need to do is list your room or house online, explain the rules and you are good to go. Travelers will pay you online. This way you don’t have to search for clients. They will come to you.
The other point is that it is pretty easy to get started.  You don’t need to be super rich, and you don’t need a lot of time to get started.  To say it requires no time would be a lie, but you don’t need to make anything listed above your life.  You can work at your job, invest your excess income, save to buy a rental property or rent out a room in your current house, and you start a side job online without breaking a sweat.
My returns are based on full cash purchase of the properties, as it is hard to compare the attractiveness of properties at different price ranges when only calculating down payment or properties that need very little rehab/updates. I did think about the scores assigned to each factor, but I believe tax deductions are a SIGNIFICANT factor when comparing passive income steams.
There are a couple of problems with direct investment in real estate though. It’s expensive to buy even a single property, a minimum of tens of thousands of dollars, and there’s no way most investors can build a portfolio of different property types and in different regions to protect from those risks when you have all your money in just one or two investments.
India's reliance on external assistance and concessional debt has decreased since liberalisation of the economy, and the debt service ratio decreased from 35.3% in 1990–91 to 4.4% in 2008–09.[293] In India, external commercial borrowings (ECBs), or commercial loans from non-resident lenders, are being permitted by the government for providing an additional source of funds to Indian corporates. The Ministry of Finance monitors and regulates them through ECB policy guidelines issued by the Reserve Bank of India (RBI) under the Foreign Exchange Management Act of 1999.[294] India's foreign exchange reserves have steadily risen from $5.8 billion in March 1991 to $426 billion in April 2018.[295] In 2012, the United Kingdom announced an end to all financial aid to India, citing the growth and robustness of Indian economy.[296][297]
For a person working for a wage, their source of income is their job, or their labor (aka their time that they sell to someone). But you can own a house, and rent it out, and when your renters pay you renter every month, the source of that income check is your rental property, or your house. It would just be called rental income. If you have money in the bank in an account that pays interest, those interest payments are another source of income. We can say the source is interest payments, or we can identify the asset that is generating rent, and say your money in the bank that is generating “rent” (aka interest) is your source of income.