@Clayton Silva Would you mind sharing more details around how he gets adu build cost that low?

Can I 1031 the 1 commercial (cannabis) retail building and purchase 20 SFR?

One of the inherent risks of new builds is locking in an interest rate.

@Marco Werner Be sure to analyze the total cost for building the ADU vs. the amount of rent you can get.

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

Real estate is a long game, and while appreciation is a powerful tool for wealth building, it should be balanced against the immediate financial realities and the market's future outlook.I hope this helps!

They need positive cashflow to help them build/maintain reserves for the downtimes.

And once you factor in interest, you are losing money since the interest alone is more than you’d get in rent once you deduct approx 50% expenses. 

If so, I would also start building your investor database and talking with as many as possible.  

In the meantime you can start building your database of potential renters.