Or, there is another theory for your primary salary – generate enough to have a little excess cash flow, but do it at a place that you can work stress free and have time to dabble in other projects.  A good friend of mine has this setup – he works 10-5 and makes $50,000 a year.  This allows him to easily cover all of his expenses, but the shorter hours and flexibility in his job allows him to pursue his secondary income generating ideas!
A lot of people these days are moving towards the two job concept. Amongst the people i know who have applied this in their life; the primary reason is that the 9 to 5 job pays their bills, lets the fire burning in the kitchen, and the second job is where their passion lies. This is the passion, which might have been forgotten while growing up, or is not a viable primary income source.
1) If your property is not under rent control, you have the ability to raise rent to market prices with proper warning. In SF, I have to give tenants a one month warning for up to a 10% increase and a two month warning for up to 60%. Rent control limits to an inflation index, usually around 2% a year, which is why initial pricing and tenant turnover is important for better profitability.
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.
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