For context , I'm a first time home buyer, and I plan on living on one of the detached units, but this calc is for when I move out in a year or so and rent out all units.

Most people in your situation go for the detached SFR owner occupy.  

Mostly because you have to do electrical and plumbing to code and most detached garages/sheds have concrete foundations with no crawl space, so they literally have to break through the concrete to draw plumbing and electrical.

Since we plan to convert garage / add an ADU to improve the cashflow later on, we look for houses with large lot, ideally with a detached garage.

Does anyone have experience adding/renovating a detached ADU in Charlotte or elsewhere?

Its better if your local but doing it abroad has its obstacles. 

She has a 24x48 detached garage I was thinking about converting to live in.

Hello All, I have a question...I purchased a property that has a detached garage in Baltimore City.

Find one with a detached garage or barn that can be turned into an apartment.

Hello Luke, I would recommend to focus on building your capital as fast as possible as thats probably the biggest obstacle for most people.