This was a perfect set up as it had a walk out basement/separate unit with 2 beds/1 bath and a kitchenette.

Additionally, for each existing and future Illinois investment property, I intend to:- Deed each property into separate Land Trusts.- Establish an Illinois LLC that will be taxed and will own the interests in the Land Trusts for my Illinois properties.- Set up a new management entity taxed as a C corporation, which can be fully owned by my revocable living trust.

We have a separate contract stating we are 50/50 owners.

You can create separate projects for property searches, renovations, and goals, and then break those down into tasks with deadlines.

You’ve got the right idea when it comes to liability protection and separating the income for tax purposes, but there are a few things to consider with the "due on sale" clause.When it comes to paying the down payment, it’s perfectly fine to use your personal account to cover it since you’re personally guaranteeing the loan anyway.

The house and ADU are close together but separated by a 6 ft privacy fence.3. 

Not unless you have them as two separate things-they pay rent like all of the other tenants and are treated the same way and you then pay them separately for the work they do.

Therefore, amounts separated for by a cost segregation study would not technically increase the "non-real-estate-property" for the purposes of the 15% test.

I'm unable to come up with a solid solution here (adding a separate gas meter is too expensive.) 

You would be best served by managing them with two separate apps.