By doing this it really weeds out the people that aren't serious and it gives me instant visibility into credit, criminal, and eviction check nationwide. 

Now, it is possible they won't abide by the lease, in which case you'll need legal help (not the cops, they don't enforce civil contracts, only criminal law and court orders). 

He basically just told that Washington state not only made it illegal but criminalized flipping and wholesaling properties and that you needs to be a licensed broker to wholesale houses.

Check everything including credit, criminal, and eviction and set strict standards.Good luck with your venture!!

I want to make sure that these new "occupants" are not criminals and was thinking about doing the following, please let me know your thoughts/suggestions:1.

You will also want to pull credit and background check (although you can't "blanket discriminate" against someone with a criminal history).(3) This is a very smart question to ask ... and yes, you want to change it over to a summer turnover.

High-tech criminals put a great deal of work and planning into this."

It's understandable to be skeptical of this applicant since he didn't mention anything about the criminal records.

—In all criminal cases, contempt cases, and other cases filed pursuant to this chapter, if a party has sold, leased, or let real estate, the title to which was not in the party when it was offered for sale, lease, or letting, or such party has maintained an office bearing signs that real estate is for sale, lease, or rental thereat, or has advertised real estate for sale, lease, or rental, generally, or describing property, the title to which was not in such party at the time, it shall be a presumption that such party was acting or attempting to act as a real estate broker, and the burden of proof shall be upon him or her to show that he or she was not acting or attempting to act as a broker or sales associate.

I would say if you are going the project manager route, then background check them, get references, criminal history, financials, everything you can.