This weekend (2/27/16) I plan to approach a seller (actually a MLS seller's agent) of a SFH in my target zone in desperate need of a rehab.

Charles... another approach is for you to buy the home, do the rehab,etc. 

There are at minimum three approaches to determining value for any given piece of real estate: sales comparison, income, and cost.

And with a post like this you are about to be approached by all of them.

.- Finance sourcesLocal to where I buy:-  Property manager, contractor/handyman, agents/wholesalersIs this a reasonable approach?

All,I was approached about investing in a condo or home that's listed on the daily county foreclosure website.

Approach a new agent who is hungry for business and ask them to set up an automatic search for you and  have the results emailed to you daily, weekly, bi-weekly, etc.  

How did that conversation go when you approached them about opening a brokerage and them being the broker of record.2.  

However, I would like to approach this with much more of a business mindset than as a one-man-shop, as my father basically does everything himself with his rentals.

This helps you approach the situation differently and understands them more. - My triplex I got w/ 10% down, owner financed for 20 years because she had small children and wanted to pay for college.