I am familiar with the Philadelphia market and neighborhoods where units trade at or around $115K/door.For this to be a true 10.5-11% cap the monthly income should be ~$10,750.00 or roughly $1,800/unit.

The remaining 40% has to be prorated.If you are not working with an accountant focused on real estate and you are focused on real estate, it may not be a good fit.

I personally would avoid the older neighborhoods closer to the post.

Rental Demand and Rates: What is the current rental demand for ADUs in this neighborhood?

Hey @Trey Holloway, there are products out there that fit the 10% down model, but you will have to hunt for one.I don't agree with @Jaycee Greene that banks don't finance STRs.

If you want predictability, value hard assets, and like the tax advantages, then investing in a real estate syndication may be a good fit.

Do you have any contractor recommendations that you think could be a good fit?  

My client is interested in investing in a new-construction build of a 23-unit apt. complex in a great neighborhood in San Diego. 

I don’t see a space for you to fit in.

You'll most likely find your staffing costs to be in the neighborhood of $1,200 to $1,900 per unit per year, depending on property size, class, and market.