I'm guessing this is why the law was added, but seems like these would fall under an ADA reasonable accommodation. 

There are a lot of these houses in the Richmond,VA. area.the best successes for residents appear to be the houses with 10 -12 or less per house although,that may not be the most lucrative model.The 4 of us(owners of 10 houses) tend to be involved in at least a biweekly basis.It is very rewarding personally but,tragic in other cases.some of us have had some "push back" from HOA's but, the ADA mention usually quiets them.I would be interested in doing more if I can find the right property.Being on the local bus line is a huge advantage

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. 

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.