I went through a divorce and now am ready to learn again.

If you can spend the time before you actually move really developing a set of criteria, you'll be ready to jump on the ideal property when it comes up. 

You noticed their vacant home and would like to speak to them when they are ready to sell.

I’m ready to succeed and some what ready to fail forward.

Is it best to open a separate savings account, run some short term CDs, or just leave in business checking to write a check when ready?

Have some savings ready to invest. 

.• See if they follow through on what they say they are going to do• When you do get a rehab, have a complete scope of work ready for them.

I am ready to proceed and my goal is to acquire my first property in the next following months.

I think a great strategy for finding seller financing is finding sellers who are not ready to retire/cash out and convincing them we’re at the top of the market, and thus a great time to sell, and that you’ll either lease to own, allow them to seller finance or pay off in chunks based on their tax goals.

Wouldn't be a terrible idea to get a short-term loan of some type to fund the repairs, and then pay it off with the refi, once appraisal ready, if cash for repairs is an issue.However, I think what you mentioned is probably the best route to go.