I'd be inclined to simply not respond to inquiries and remove the ad as soon as it had accomplished whatever I had wanted to test.

ADA: doesn't cover "emotional support animals" at all.

Be sure to comply with the American with Disabilities Act (ADA) and Fair Housing laws.

I am a formidable force to deal with when prospective tenants illegitimately try to use the ADA and other non-discrimination laws to their advantage.

Guide dogs & service animals are covered under Federal ADA.

If they have not confirmed an hour prior to their appointment, I send this text to their phone (which was required as part of their contact information I required in the response to my ad):As I had requested in my email, you have not yet confirmed your apartment showing for this evening, scheduled for 7:00pm.

We have to be ADA compliant and we forgot to pour the concrete for the road higher to meet the office. 

You'll have better luck looking in Canyon County (Nampa, Caldwell) for inventory, and vacany rates are currently better out there than Ada county. 

Most people who claim to have a service animal are claiming emotional support animals which is not recognized as a service by the ADA and you do not have to accept them. 

I understand where Thomas is coming from.I would, however, recommend you consult your attorney regarding your responsibilities under the ADA (Americans with Disabilities Act), if any.