Sure you can find rental properties under 100k still but they most certainly will not be in a desirable area.  

The neighborhood is about 10 minutes form a lesser desirable area to the east (across a freeway), and the main road is busy/larger.

Long Island will always be a desirable market. 

A brand new building with commercial space on the first floor could mean new restaurants, shops, and businesses for the neighborhood, all of which would mean the area would become a more desirable area to live, and your property price would likely benefit as a result.  

We’ve been tossing around the idea of converting one of our bedrooms into a gym (treadmill, weights, bench, etc with towel and water service).

investors holding a note secured by a assisted living facility will require an interest rate of 9 - 14% depending on desirability of property and strength of operator/borrower.  

We have some properties in LLCs but it is always because our bank has required it not out of our desire.

You get the benefit of 2 years+ of appreciation, tax free gains, protect yourself from buying in a crappy neighborhood because it looks good on paper - you're going to live there...the best test for a good investment location is if it is a desirable place to live - and your risk of running out of cash is lower because you can take your time.

So finding the cash flow you desire will be far more difficult.  

circumstances.. education.. personality .. innate abilities.. lack of understanding basic math..desire .. drive.. familial pressures..