With that in mind, I’m considering purchasing four rental units over the next four years to build a stream of income that could help supplement my retirement by age 68.The challenge I’m facing is that the deals I’ve come across so far don’t make financial sense.

It seems like you have some very solid goals of multiple income streams, and a well calibrated risk tolerance. 

We've had develpment plans with stream and wetlands crossings, which required both state and Federal permits. 

I would still need to subscribe to a streaming service for cable tv, so cost savings wouldnt be much (or a wash), but otherwise it seems like it might be a viable alternative?

If this were a Real Estate secured note,  a note broker or flipper might offer you up to about 65% of the remaining balance whereas an investor who is building passive income streams week offer up to about 90%. 

However, vacancy means covering 100% of the expenses.Multifamily properties almost always generate higher cash flow due to multiple income streams, which also reduces the risk of vacancies.

There are areas outside the Tahoe basin with a short drive that can provide for solid short term or long term income streams and still pull in the Tahoe goers.

A CPA ensures compliance with IRS rules, maximizes deductions, and avoids costly mistakes, especially for higher-income earners with multiple income streams.

Real estate investing has been a passion of mine for time with my mother also having invested early on where I likely have gotten the love and desire to follow similar foot steps.I have taken last 6 months to educate myself and currently own a single family home as primary residence and would like to expand to multi family properties (2-4 units) for additional stream of income, not to mention potential tax benefits for long-term investing.Based on current living situation, I have a fair amount of equity established in my primary residency along with having enough cash to either pay off house completely or use towards investing in a multi family property.Given that I'm the sole source of income for our household with my wife being the home maker for our two kids under 2, trying to weigh out risks with getting started now or perhaps waiting. 

I'm looking to make this part of the retirement stream of income rather than an effort to accumulate multiple properties.