When I have dealt with the IRS they have always wanted to see paperwork, so I try to get as much paperwork as I can.I get business cards from everyone I talk to, keep receipts from meals and some type of business log who I meet with and how I traveled there.I have found they prefer a log that was created at the time I was traveling rather than something that was created sometime later.

Because your activity right up until renting will act a lot like a developer there will be a natural skepticism on the part of the IRS if ultimately audited. 

The IRS link while helpful to provide general information is not authoritative as I'm sure you're aware, and should be read in this context.The statutory guidance on what constitutes a partnership is vague. 

Here in CA I believe the tax sale wipes out pretty much all previous liens EXCEPT that for 120 days if the IRS has a lien they have the option of redeeming the property for what the bidder paid.

Opportunity zone funds have several rules in place to be able to meet the IRS guidelines.

Reference IRS publication 598.When a 401(k) receives gains from an investment that uses debt-financing, it can be creating Unrelated Debt-Financed Income (UDFI). 

You'll figure that by first taking the lower of purchase price or retail value on the day you put it into service  as a rental I believe (a lovely little "getcha" from the IRS). 

Now tax season and I need help with separating my receipts and paperwork that will be good for the irs and help me in the long run.

And just to add to my previous statement it's a great idea to have your CPA put together a draft of what he/she is about to submit to the IRS. 

@Daniel EvenchenWhat you propose would violate the IRS rules.