However, under certain circumstances, payment for personal services performed in the United States is not considered income from sources within the United States. For example, personal services performed by an independent nonresident alien contractor specifically exempted by a tax treaty. For more examples, see the Pay for Personal Service section in Publication 515, Withholding of Tax on Nonresident Aliens and Foreign Entities.

While it is important to find something that you love to do and turn it into a money making business, you do have to be cognizant of the return as you pointed out. There are many opportunities that I found and tried out that at the time seemed great. But when I took a step back, I realized that I was working a lot for very little income whereas other things I love doing brought in much more money.

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.

Agriculture is an important part of the Indian economy. At around 1,530,000 square kilometres (590,000 sq mi), India has the second-largest amount of arable land, after the US, with 52% of total land under cultivation. Although the total land area of the country is only slightly more than one third of China or the US, India's arable land is marginally smaller than that of the US, and marginally larger than that of China. However, agricultural output lags far behind its potential.[367] The low productivity in India is a result of several factors. According to the World Bank, India's large agricultural subsidies are distorting what farmers grow and hampering productivity-enhancing investment. Over-regulation of agriculture has increased costs, price risks and uncertainty, and governmental intervention in labour, land, and credit are hurting the market. Infrastructure such as rural roads, electricity, ports, food storage, retail markets and services remain inadequate.[368] The average size of land holdings is very small, with 70% of holdings being less than one hectare (2.5 acres) in size.[369] Irrigation facilities are inadequate, as revealed by the fact that only 46% of the total cultivable land was irrigated as of 2016,[158] resulting in farmers still being dependent on rainfall, specifically the monsoon season, which is often inconsistent and unevenly distributed across the country.[370] In an effort to bring an additional two crore hectares (20 million hectares; 50 million acres) of land under irrigation, various schemes have been attempted, including the Accelerated Irrigation Benefit Programme (AIBP) which was provided ₹80,000 crore (₹800 billion) in the union budget.[371] Farming incomes are also hampered by lack of food storage and distribution infrastructure; a third of India's agricultural production is lost from spoilage.[249]

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.
India is a founding-member of General Agreement on Tariffs and Trade (GATT) and its successor, the WTO. While participating actively in its general council meetings, India has been crucial in voicing the concerns of the developing world. For instance, India has continued its opposition to the inclusion of labour, environmental issues and other non-tariff barriers to trade in WTO policies.[286]
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Inspired by you, I started a tax/personal finance a month ago. I figured if it works out, it will create a good side income for me. If not, at least I can use the blog to build my brand as a tax lawyer. Other than that, my current investment portfolio is heavily focused on index funds because of its historical performance and tax & cost efficiency. Right now my dividends income every year is about $14,000. I also have a good amount of unrealized capital gains every year from my investment, though I don’t count the capital gains as my passive income as they are paper gains, at least for now.

I’m looking at accepting a professor job. It’ll be more than a 50% pay cut. But I’ll have the same life you describe – endless summers and an entire month every winter to ski. I’m thinking in the end, eventually, I might even end up wealthier in more ways than one. Happy people tend to be the most successful. I have no desire to diversify. Dividend stocks allude me. CDs seem like a good choice for older people, but I have time on my hands and real estate knowledge, so I’m sticking with what I know, despite the fact that most people will tell me it is foolish and I should diversify.

In focusing on your wealth management goals, investment income is obviously critical but you might fund your goals from wider sources of income.  A typical long-term portfolio might produce about half its return as income and the other half as capital growth, though in times of duress the capital growth component wanes.  In this low-interest rate climate, some sources of income have become quite expensive and may prove disappointing against your spending needs.  But by tax efficiently and sustainably drawing income from wider sources, you might meet your goals while more prudently balancing risk against reward.