You might consider rolling your Traditional IRA over into a Solo 401k and purchasing a property with debt, instead of IRA.

I wondered if SF route might allow us to secure better terms at maybe a 4% interest rate for a few years on the funds not rolled into current $150k potentially assumable mortgage -- and in a few years we could roll into a traditional mortgage. 

Furthermore, you'll obtain better financing rates/terms with a primary home loan than with an investment mortgage product.To get the ball rolling, connect with an experienced house hacker and investment-focused real estate agent in your market ASAP. 

With you getting the ball rolling you need to get properties under your belt and get the snow ball rolling.

@Nathan Gesner Conducting a quick test.

So you are just choosing one retirement vehicle over another.You can also consider rolling the 401K into your new employer and take out a 401K loan if your employer offers the option.You would normally be eligible to take a loan of the lessor of $50,000 or 50% of your vested balance which would be $4,500.Best of luck

Or in the early stages ask for more detailed financials for the last rolling 12 months, and come back with that data early in the process to weed out those who won't budge?

I’m not sure if I should accept the offer and roll my equity in a new property or just sit tight and see what happens?

If you meet this first test, you are a REP...now determine if you can use the benefits of it.2) if you or your spouse meet test 1, THEN you can make an election to combine all your RENTAL activities together for purposes of determining if materially participate in your rental activities.  3) So you met test 1, made the election under #2 - now you see if you materially participate in your rental activities. 

There are 7 material participation tests and these are the 3 most common for real estate investors AND you need to meet one of them: Spend more than 500 hours on your rental businessDo substantially everything for the rental businessSpend more than 100 hours on the activity and no one other individual spends more time than you doAnother way to offset non-passive income (e.g.