You may want to look up @Marcia Maynard, she has phone interview prescreening questions.I think it is reasonable to ask some questions to weed out some applicants that would be time wasters - how many people in household (without asking for number of kids, marital status, etc), pet situation, household income (without asking type of work/source), etc.  

So the animal does not have to be wearing any ID to signify that they are in fact a service animal.

You just have to make sure you're not approving/declining an applicant based on race, color, sex, religion, creed, national or ethnic origin, age, familial or marital status, handicap or disability or sexual orientation.  

I would be very likely to have it done if there was no currently broken glass in the windows (signifying "possibly" that your tenant does not value the property enough to be careful). 

Not a lawyer, so no legal advice, but if he is not breaking any city rules or regulations by having the RV there so long, then I believe this is just a blatant sign of a major marital issue between you and your wife.  

Here is the Seattle definition: “Discrimination” means any conduct, whether by single act or as part of a practice, the effect of which is to adversely affect or differentiate between or among individuals or groups of individuals, because of race, color, creed, religion, ancestry, national origin, age, sex, marital status, parental status, sexual orientation, gender identity, political ideology, honorably discharged veteran or military status, alternative source of income, participation in a Section 8 or other subsidy program, the presence of any disability, or the use of a service animal by a disabled person.

The tenant was caught in several lies (rental history, wrong SS#, marital status, previous state of residence), including an explanation about a charge of "theft by unlawful taking" that showed up on her background check with no disposition.

Maybe there are some states where the deed is like the "pink slip" for a car, but in the states that I do business in, the "deed" signifies the "transfer" from one party to another, it's the RECORDING of the deed that's paramount.Unless you're an attorney (and it doesn't sound like you are) call a TITLE COMPANY/ESCROW COMPANY (or a RE Agent and ask who does ppty transfers in your community) and get with them.Let me give you an example of how it's done in TX and other "Trust Deed" states.

A divorce and subsequent short sale of the marital home tanked my credit then a job loss added a ton of debt making me unattractive to banks.

These often signify potential for renter demand.2.