I have no doubt that if I could find an accredited investor or non-bank lender I'd be able to secure funding.

They are senior to their debt, so they can crush, make sur there are's any other secured interests on the property. worth the $100 or so for a prelim title report. 

I have found some sites provide considerable due diligence type information and others treat it like a national security secret. 

I have an ITIN, but no Social Security number as Immigration just delay and delay.

Otherwise I go through after they leave mark up the security despot and send it back. 

This is always a good way to ensure that you get the type of people that would like to be living in your property.

3. is it OK to ask a tenant to bring a certified check, as her security deposit ?

If not, he can sell it to you and carry back a note secured by a 2nd deed of trust.

Nevada secured over $150 million to help qualified Nevada homeowners.The U.S.

Below, are a couple guides for your review. https://www.biggerpockets.com/renewsblog/2007/11/26/demystifying-the-real-estate-rental-security-deposit/ (Security deposit laws)http://www.biggerpockets.com/renewsblog/2013/01/04/how-to-rent-your-house/ (house rental guide)