I would contact the "prolific investor" I am sure they have far better insider insight into the machinations of AIM rather than the internet reviews of denied/disappointed applicants.

And how do you prove so in court if tenant denies the claim?

I know some people will do it to abuse the system when it comes to rentals just so that the dog is allowed wether the owner allows it or not

I can't describe how many others I denied for having pitbulls, rottweilers, etc. 

this way yaddah - possible but "The bank" has only told you yes when the cash is in your hands or finally denied.

They denied it and asked that I prove it.  

To summarize the comments...1) You can't say no2) Charge them more (Dont say no)3) Demand a background check for every adult (Dont say no)4) Deny on a different basis (Say no)Your saying you know all the laws governing denial of said applicants, so nix point one and just deny them for whatever reason you deemed legal.

Assuming their credit is good, I want to deny them based on this issue of two kids down the street and all her friends and taking over the property, etc.

.- Illegal, loud, harassing, abusive profane or otherwise disturbing conduct by the Tenant or guests of the Tenant shall be attributable to the Tenant and shall constitute a violation of the terms of this Lease. - Pest control is not provided by landlord.- Common areas should be quiet after 10 p.m. to not disturb the piece and quiet of other residents.Is there anything else I should include in a shared tenant/landlord dwelling like this (aside from the standard lease terms, such as damage and indemnity and so on)?

These are good people who aren't really abusing the system.