I currently have a duplex in Milwaukee and am living in a single family home that I plan to turn into a SFH rental.

If you are single or married with a small child, buying a duplex or 4plex should work well.  

There are also several funds out there that provide high single digit yields that are low risk. 

I made the mistake of renting my single-family house in Alpharetta to a tenant with a credit score in the 500s in December 2023.

If you are single or a couple on the same page about house hacking, look for uneven multis.

The ADU is a good idea for property maximization, but unless it has a separate driveway, it will push your rent in the main house down some because then you aren't renting a single-family house on a lot by itself.

In Ohio you can find a lot of single family in the $100-200k range or 2-4 units in the $150-400k range that do pretty well cash flow.

You really don't know a single thing about Real Estate do you John? 

I don't think you are going to be able to get insurance for two separate living units in a single-family when they are both illegal and likely do not have the correct egress windows (basement) for fire safety which could subject you to huge liability if something happens to either party.

Didn't appreciate it would have to be that many doors multi-family vs higher value single family.