I am very interested in multi-generational houses or especially homes that are easily convertible to allow for a junior attached ADU per California's definition.I have searched through literally thousands of house plans and noticed that very few of them have this ability.Has anyone else attempted to do this? 

Advantages are you can generally afford one house more easily than a multi, easier to finance, generally more sought-after and whole categories of issues are non-existent (ie noise of upstairs neighbor complaints).

Half of them are wrong, and the other half are easily misinterpreted by the non-practitioner.

Chicago is EXTREMELY neighborhood and block specific, so the data can skew quite easily. 

They fly by the seat of their pants just like any mom-and-pop investor.I manage 400 rentals so I bring a lot of experience.

With some upgrades to the upstairs I could easily get $1500/mo next year as well..bringing my monthly cashflow to about $1,591.

I can see this coming around to bite you pretty easily.

Is that the kind of thing that can be cleaned up easily?

I do find that I can beat the numbers fairly easily by running the property right.

My partner lived 5-6 blocks south of that at one point and I locked my bike there for 15 minutes and my bike seat got stolen.