I get the feeling the 1031 is the smartest financial move, but I'm not sure how much time and energy I'll have to put into it, particularly since I don't personally believe the Seattle area is a great place to invest in any longer.

Whereas I just wanted a clean financial transaction.

They are obviously financially struggling which makes them high risk.

If you are comfortable with that type of relationship, then the pool of qualified CPA's really opens up and you stand a better chance of finding someone who fits your style. 

If you utilize seller financing, you can sometimes get the seller on board because they get their sales price and you get favorable loan terms2)  They don't need the cash right now (retiree, empty nester) and are financially astute enough to see how collecting interest for 5-10 years on their note can be very profitable.Which argument works completely depends on what the seller needs.   

I'm likely going to be a Trustee and I'm wondering if there is any financial advantage to my Dad creating a corporate entity and transferring the house to the company, and then the company to the Trust. 

You spend more time.Start with QuickBooks, as you will know your numbers - equity and financials.

I have known real estate is one of the most proven ways to financial freedom for many years now.

I was a little worried that if I had a HELOC for the down payment then the banks or financial institutions would look at it as a loan on top of a loan.

Determine what your emergency fund (CapX) number should be, then fully fund it before you start taking money out.I know many in this forum don't go about it this way, which I also understand as well from a purely financial side.