What will be some of the  tell-tale  signs  that will stand on the obvious side  and what may be   some of  those  signs that  are more subtle after the smoke clears.

While talking to him about further art pieces being displayed in the future I mentioned that he seemed very young and successful at investing in real estate( I looked at his companies instagram and his personal instagram).

That's a scary fairy tale that went well.

We returned to the USA (San Diego) in mid 2016 and lived the retired lifestyle (wake up at 9am, cook & eat breakfast, check Facebook/Instagram/Snapchat for 2 hours, take a nap, wake up at 3pm, work out, take a shower, eat dinner, hang with friends, repeat).

I haven't tried instagram ads yet but depending on your target demographic, that could be a useful tool as well.Best of luck to you!

The owner is selling due to an appearant seller financing deal cautionary tale.  

you get to listen in for free on his YouTube and podcast, instagram etc.

What is a good tell tale sign of a solid probate lead, how do I spot a good pick from the pack?

With cash you can close faster and sellers like a faster closings' instaed of having too wait for the banks etc. 

I do this to grow my business and find maybe ten new investors a month but truth be told I have received so much more business from craigslist, BP, Facebook, Instagram, snapchat, and meet up events (tax auctions, REIN, etc.) which is the point of some of the posts above.