You will need a strong team in the city and someone who has a good reputation that can be tarnished if they swindle you. 

You are walking a very fine line that usually doesn't get tripped up... until Sammy the third cousin twice removed on Auntie Jane's side decides that you swindled Auntie Jane out of what her property was REALLY worth when you put it under contract and then sold that off for a profit instead of listing it on the MLS as an agent should do.  

But make sure you are dealing with the actual owners of the property this time.As for the $12,000 you have been swindled out of, obviously I would put a stop payment on the check, file a fraud complaint with the bank, and get a lawyer/LEO involved.  

Got burned, bamboozled and swindled and had to toughen up.

Do some people get swindled?

The lack of licensing requirements, oversight and the ability to swindle some pretty stunning amounts of money from uneducated sellers is exactly what attracts a lot of wholesalers and gurus in the first place.Believing that there isn't a large majority of wholesalers who are deceptive, dishonest and do nothing of value in a transaction is just nonsense.