I agree with Chris, you really can't create an average to go by.

The HVAC tech was able to take apart the vent pipes in the attic, but was unable to go on the roof and check the top portion of the pipe or change the vent cap.

Is there anyway to calculate the end investor's desired yield of 8-14%?

ARVs pushing right up toward the median now, so you really have to go subdivision by subdivision, or even street by street, to get a feel for which areas are rental areas and which might be better for low end flips. 

You aren't far off, but if that it the maximum that you are willing to go, then it probably isn't going to happen. 

just have to go through the quiet title to please the title insurance underwriting criteria.some title companies make you wait a year before they will even consider it some 5 years.in SC it looks like this lady is going to be over 5 years.   

Then you'd have lots of options to go with: cash flowing rental, BRRRR, sell. 

If you don't have enough capital to obtain financing, you'd need to go with the owner financing deal.

If you have a licensed contractor-friend ask them to go with you on your first walk through, they are a valuable asset on your team as well.

You might also want to go down to the city's zoning department and try to talk to someone there.