There are tests you can buy on Amazon, where you can swipe it on the walls to determine residue.

My acknowledgement of investors seeming happy was based on internet discovery. 

Then determine your burn rate, days between call to cash, take down ability and average profit per opportunity. 

What i cannot determine is why.  

Quote from @Levi Perl: The purpose of background screening is to determine a level of risk, and then you decide if you can mitigate that risk.How does a DUI conviction from three years ago impact the tenant's ability to pay rent or maintain the property?

Oh look, you get to deduct your cell phone, your internet, your tax prep, all kinds of other things regular people don’t. 

If there is no initial agreed-upon amount, determining a fair compensation becomes more time-consuming, leading to further losses.

To gain investor confidence, ensure the investment property numbers are real, use the most common contract forms in your state (versus a 2 or 3-page) internet/guru contract form) with appropriate addenda, or an attorney-drafted form and attorney-drafted assignment agreement.

Whether your statements are true or false, whether we have evidence to support or deny a claim, it will never be something blasted on the internet.

I came across following idea from internet about buying defaulted mortgage notes directly from banks.