Anyway, I have a SDIRA set up as an LLC for rental property purchase in Nov 2016.

What was the one idea you stuck with that produced your fortune over time?

You should only leverage to the point where the investment can still create cashflowIn reality a property that can not produce positive cash flow with a hypothetical 100% financing can never produce positive cash flow without a abnormally high rent increase.

Each time, society convinces itself that the current boom, unlike the many booms that preceded catastrophic collapses in the past, is built on sound fundamentals, structural reforms, technological innovation, and good policy"

If you have enough reserves in the bank to do so, I would try to just see if the bank has a mortgage product that doesn't have to look at your other income outside of what the property you're interested in purchasing produces.

My question is what records should I feel comfortable in asking the seller to produce, so I can do diligence. 

It is all made up - a lie....Unless he produces the paperwork.

One day I was brainstorming, and I remembered that my parents have a rental in Farmington NM, that is just sitting vacant, that they use as a storage; trust me I know, its crazy to let an investment that could be producing cash flow, just sit and do nothing. 

They already exist edit - 3d printed houses are fantastic innovation and quite useful to low/no income or temporary housing and other uses.

What are you doing in California with the cheapest property value being almost $300k-$500k to produce enough income to put down 20%?