What is good about a corporate Guarantee is name recognition/PERCEPTION,  decent financing, and higher value if you are a seller.  

All this info is public data and strongly recommended due diligence.  

This is a Public Service announcement. :-) Not to worry, the public will move to where they can afford to live and that will affect prices up & down the scale. 

.- Robert-Lee don't buy in rural anywhere. property values are lower, rental interest is lower, new construction comps are harder to come by. we build in Columbus Ohio and the things I look for are subdivisions within 5 miles from a large builder delivering at least 2 homes a month or more, 30 miles or less to the city center, public utilities, no flood plain, etc.

It used to be publically available from an active realtor on Bigger Pockets, but now I can't find it.

Being an agent is great, you get a deeper insight to the market and see things come up before the public.

You're Welcome 😉IRS Publication 544

I'm a web developer, trying to figure out the best source to find properties in say, Virginia that have been sold twice in the last 18-months, with the idea being to find flippers and contact them.Any ideas on publically available data sources?

., the same as you would any publicly traded stock.

I suspect the sources you are referring to are the same who educate others on associating with more established sponsors to give the perception that more of a track and experience exists.