(He has not taken a salary from the nonprofit in 20 years- but the proceeds go to a cause he cares deeply about)  Currently, my sibling and I own 40% of the building, and the nonprofit owns 60%.

How would I go about analyzing, building, financing a project to attract well healed boomers?  

This is for fun and entertainment not financial advice please consult with your advisors.If you want to find some options head over to the build your team tab to find tax and finance pros.  

start building a basic underwriting spreadsheet so you can play with the various deal inputs, test out different scenarios, and see how they perform financially.Analyzing deals is the only way one really learns to think like an investor!

He now talks about brand new homes he builds in Texas.

Con's- more expensive monthly, locking us down to CLT/ condo building for what I am guessing at least 5 years to at least make it worth it. not as much revenue/wealth building opportunity as duplex

Verifying last 2 years of rental history and income extremely important to find the “best of the worst”.Make sure you understand the Class of properties you are looking at and the corresponding results to expect.Also, connect with @Samuel Eddinger in your area as he's experienced in building portfolios and managing them.

I’m a registered nurse in New York City, new to real estate investing currently in the process of learning and building my knowledge base to make my first real estate purchase.

This is the Old West End, a historical district in Toledo that has a very strict HOA/Historical Protection group that basically forbids you to use most modern building materials.

I did use credit cards to help build my portfolio.