I would throw in some caution here: if your spouse works at the same company, or in the same industry as you, you are not diversified, and should something happen, you could be in a world of hurt.  Companies do go out of business, companies do lay employees off.  There is nothing wrong with working together, but realize that you are not diversified and you should be trying to maximize other income streams as a result.
The reverse can also be expected unless the rents rise too.  This rental increase might occur if we imagine interest rates are rising because the economic environment is improving.  At present, it is widely expected that rates will rise ever so slowly over many years.  Indeed the US has been looking for the courage to do this over recent months and they may start rising there soon.
The International Accounting Standards Board (IASB) uses the following definition: "Income is increases in economic benefits during the accounting period in the form of inflows or enhancements of assets or decreases of liabilities that result in increases in equity, other than those relating to contributions from equity participants." [F.70] (IFRS Framework).
According to Uncle Sam, you need to be "materially involved" in an enterprise to earn active income. With passive income, it's just the opposite, as the IRS deems you to be earning passive income if you're not materially involved with a profit-making enterprise. By and large, expect income to be taxable if you are engaged in a passive income enterprise. You will need to report earnings to the IRS.
You can make money whichever way floats your boat. I got a lot of slack in this post for trading forex, but I live in one country, and need currency from three other countries where I own property and travel to often, so when one currency is cheap, I do take advantage of fluctuations. It may not be your thing, but the important part is that you have more than one source of income.
Seven of the ten counties in California with the lowest per capita incomes are located in the Central Valley. Two of the remaining three are rural counties in Northern California. This leaves Imperial County, which shares California's portion of the U.S.-Mexico border with San Diego County. All of these counties had populations not exceeding 1,000,000, and all of them are landlocked, with the exception of Del Norte County.
India has made progress increasing the primary education attendance rate and expanding literacy to approximately three-fourths of the population.[389] India's literacy rate had grown from 52.2% in 1991 to 74.04% in 2011. The right to education at elementary level has been made one of the fundamental rights under the eighty-sixth Amendment of 2002, and legislation has been enacted to further the objective of providing free education to all children.[390] However, the literacy rate of 74% is lower than the worldwide average and the country suffers from a high drop-out rate.[391] Literacy rates and educational opportunities vary by region, gender, urban and rural areas, and among different social groups.[392][393]
Others may define it more narrowly, but to me, PPC arbitrage basically involves setting up PPC ads (via Google AdWords or similar platform) and directing the traffic that results from ad clicks to a landing page or straight to an affiliate link (which many platforms don’t allow anymore).  The goal is obviously to earn more from the affiliate income than spent on the ad clicks.  You aren’t adding any value, but merely earning more from traffic than what it costs you to generate that traffic.
India is one of the largest centres for polishing diamonds and gems and manufacturing jewellery; it is also one of the two largest consumers of gold.[183][184] After crude oil and petroleum products, the export and import of gold, precious metals, precious stones, gems and jewellery accounts for the largest portion of India's global trade. The industry contributes about 7% of India's GDP, employs millions, and is a major source of its foreign-exchange earnings.[185] The gems and jewellery industry, in 2013, created ₹251,000 crore (US$35 billion) in economic output on value-added basis. It is growing sector of Indian economy, and A.T. Kearney projects it to grow to ₹500,000 crore (US$70 billion) by 2018.[186]
Thirst for income is likely to continue with interest rates expected to stay low, keeping government bond yields low for longer and their valuations unattractive.  Looking past bonds, the prices of high-dividend shares are historically high, which limits the likelihood that their dividends will rise markedly from here.  Striving too high for an income target tends to push your portfolio further out on the risk spectrum.