I would send any suspicious pics to the owner for discussion.

Regular checks allow you to correct these.Identity Theft Protection: Spotting unfamiliar accounts or suspicious activity can be a sign of identity theft.

His communication is horrible and he suspiciously asks for lots of money upfront.

Once we have leads, I cold call them.I'm suspicious that Facebook ads might be a better way to generate motivated sellers, rather than cold calling, though.

And that's what I'm suspicious of in MFH. 

If cops come it would probably be an easier conversation than "I need to talk to you because you don't want to talk to me and I'm suspicious now." 

I'm looking at my first properties, and have been cautioned by a friend to avoid a duplex that looks good because it does not have a rental history.A granny owned the duplex, and since she died one of her adult grandchildren has been occupying the property, leaving the upstairs vacant.My general question is, do you look suspiciously at vacancies, or disregard them if you find suitable reasons for the vacancy??

I'm always a little suspicious of people who have lied to me.

This way the seller won't get suspicious with all the people coming to look at it.

This property is just one of those rare deals where the bank made a huge folly, and it probably took them a long time to realize what went wrong, especially when they could've seen that the property was suspiciously still standing two years later (the bank was very local).