I attribute this to a couple of things, but I could be wrong:1.

-----attributed to PT Barnum

Maybe this attribute (the "turnover rate" characteristic) of the neighborhood dynamic doesn't matter that much.

For the brief scenario described, assuming the reason for using private money upfront, then refi months later is attributed to time for rehab, a renovation loan seems to make the most sense: this type of purchase loan is based on ARV!

(same attributes as the house Im getting under contract) sold for $60k.

Those are some of the great attributes that successful people are made of, and I am proud of you, as I am sure a lot of other people are also.There are always many different path to success, some more or less risky than others.

For others who do this, what attributes do you consider when deciding whether to hold or to sell?  

For sales of depreciable real estate, a maximum federal rate of 25% applies to the portion of gain attributable to your depreciation deductions.

Sounds like "diligence" is a worthwhile attribute.

Many times, this can be attributed to varying situations (eg. contractor was booked when you closed, did not have financial means to carry a 2-draw streamline/limited 203k construction note).