In addition, if you are self-employed with no full-time employees you may wish to consider opening a Solo 401k instead of a self-directed IRA as it has several advantages over an IRA LLC such as much higher contribution limits, direct checkbook control (i.e. no need to have the account at a specialty trust company), ability to take a 401k loan, exclusion from unrelated debt finance income tax with respect to investment in real estate acquired with non-recourse financing, etc.In addition, please note if you purchase debt-financed real estate with your IRA, unrelated debt finance income tax should apply to the income attributable to debt-financed real estate held by your IRA.

You would then get the title insurance under the name of the LLC and yours at closing as suggested by your title company, and then later you could add your other partner in the company.If the LLC already exists, you can create a new one and then sell/contribute it to the holding LLC.It becomes more complex but it gives you a way around. 

In the BRRRR podcast, episode 327, David Greene made a comment (1:08:30ish) suggesting his single-family homes tend to add equity for him and his multi-family homes contribute more cashflow.

It can help with taxes now if I contribute to a defined benefit retirement plan. 

The notion that we must live in close proximity to our job sites has, for millions, just been proven unconditionally false.

I want to start putting 100% of my distribution into the 401k as a ROTH contribution.

It works a bit  like a 401k contribution works... you get an up front tax benefit when exchanging if there being no tax when you go into the 1031 exchange...but when you sell the property you exchanged into, tax is due on both the profits of the first deal, and the profits of the second, etc.  

One reason that almost all business sales now-a-days are structured as asset sales, not entity sales.If you do buy into his LLC, assuming it's disregarded for federal income tax purposes, we treat it like this: (1) an asset sale to the existing holder, the buyer obtains an undivided interest in the LLC assets and simultaneously (2) the buyer and seller (members) are deemed to contribute of each of their undivided interests in the LLC assets and liabilities into a newly formed partnership tax entity.There isn't a 754 election available in this situation, as a partnership interest was not what was sold for tax purposes. 

We max our traditional retirement plans (401k's, IRA's,) and contribute regularly to a brokerage account.

Make sure it includes everything about how your business will run, what each persons responsibilities are, who will contribute what, how profits will be divided etc.