A friend did a drive by of the property and apparently there is someone living there and they were acting ‘suspicious’ of a strange person driving by and scoping out the property. 

@Przemek @Przemek Kos I would agree with Rich, I would be suspicious of 5% unless the deal was less than 1 m.

However over the years the IRS has been very suspicious of such arrangements because of the opportunity for friendly parties to structure sales prices to shift the basis to benefit the exchangor. 

I thought it was a bit suspicious if they matched the 1500 they could stay and could just be used as a loophole to unsuspecting tenants.

A neighbor is a good choice with an added benefit – they can let you know if anything suspicious is happening around the Airbnb rental property.

If not, I'd make 100% certain that estimated rent is accurate.The lack of down payment, the interest rate, and the term of the note make me highly suspicious.

Kastle’s Remote Video Guarding generates early alerts to suspicious activity notifying operators when people loiter near the bicycle storage areas.Live monitoring is effective in this instance to gauge context such as someone spending too much time in the area or returning several times, which could be an early indication of threat.PETSFrequently, resident pet owners are contractually obligated to clean up Fido’s waste—not doing so is not only a discourtesy, a maintenance headache, and a potential health hazard, but it’s also a lease violation.

He says, "I noticed a suspicious plastic bag with white substance on the sidewalk.

I don't have all the details here, but this is highly suspicious. 

Let’s just say the guy keeps coming in and fixing it for free, but small things keep happening to the refrigerator, which has the guy suspicious the tenants or maybe doing something.