I'm sure you already know this, but "turn-key" and "scam" are very much hand-in-hand. I have had the most luck with contacting business brokers off-line and having them do the hunt for me, and me doing searches and finding businesses that I am interested in and picking up the phone and calling direct. Leave email out of it. Use Alexa to find their phone number if it isn't listed on their site or in the WHOIS info. And one more piece of advice. Let them do all the talking. Sites that you would pay $5k for, they will let go for a few hundred dollars.