It isn't having paid off properties that offers security, there are still taxes, insurance, maintenance and management involved. 

Nothing illegal about doing that, but if caught, the lender may call the loan due and if you don't correct the situation or pay the loan off, they willstart mortgage foreclosure.3) You could also go the HELOC route to tap the equity in the home, but the 12-month owner-occupancy will also apply AND the interest rate on the HELOC will fluctuate with the Fed Fund Rate.4) You could do a cashout refi as an investment property, but that will be at an interest rate 0.5-1% higher than owner-occupied rate.Suggest you meet with 2-3 lenders to explore your options about the above.Once you have access to funds, recommend you buy a 2-4 unit with 20-25% down. - You can buy owner-occupied, live in one unit, and fix up and rent the other unit(s).- If you're handy, recommend buying a property in the worst condition you can tolerate.

Applying that to RE investing, most would agree your first FHA loan should be a multi-unit house hack.

Legal and Regulatory HurdlesReal estate transactions involve legal complexities that can overwhelm newcomers.Solution: Learn about legal requirements early on and seek professional advice when needed.

I also had horrific PMs, particularly involved with a 48 unit apartment complex in Houston.  

Real estate is transactional where people are involved so it won't be a black and white answer.The best to do is to find an agent that fits your needs and guide you through the process.

Enclosed a few pics for your reference.Should I involve the HOA?

Again, there's time and cost involved because they are unlikely to get everything.4.

Learn what each one of these are, and see which makes the most sense to apply to your specific financial plan. $150 cash flow on any rental especially a triplex is dangerzone imo. 1 month of vacancy of 1 unit could destroy a years worth of financial gains.  

Otherwise, if you are referring to ETF's such as Spiders, or QQQ, the the holding period rules apply.