But now I see no alternative. 

This new alternative setup would be quite simple: Oakbrook PM LLC adopts QRP (Solo 401k)As part of the plan creation we would create a trust with the purpose of holding plan's assets You become the trustee of the trust (which give you power and control over all assets and investments)Trust will have it's own EIN (single number)Both you and your wife will have separate accounts as plan participants under the same trust (there is no additional cost for another plan participant)Also, each of you can have separate Roth accounts under the same plan, if you chose to make post tax contributions or do the conversion (there is no additional cost for Roth sub-accounts, that comes with every single plan)By doing truly self-directed Solo 401k plan you would have significantly reduced your cost, simplified the structure and gained more flexibility!

But another alternative is to use an equity loan or line of credit, as some banks will do a higher LTV. 

@Talha K. from experience with human beings, we always scout at least three other property management alternatives who can jump in and take over at any given time.

Seems like a very attractive alternative and a fraction of the price.

I recently graduated nursing school (hello job security) and I want to invest in real estate. The problem is I'm having trouble getting my first full time job- my lovely school messed up three times and screwed me out...

Tumbleweed Tiny Homes are popular in California.

Remember, to reach a location there are often alternate routes you may take and you may find that the current route you are on is not the best fit for you; all that truly matters is that you still get where you are trying to go. 

You may find that certain sites are more popular in your area, so it's good to try out a few.

So 2 remaining types of accounts are what I need to do further research on.When I google SDIRA I get this in the most simplest of definitions:A self-directed Individual Retirement Account is an Individual Retirement Account (IRA), provided by some financial institutions in the United States, which allows alternative investments for retirement savings.It appears though that the SDIRA has a component of allowing 'checkbook', no?