Deny.  

you can retain the security deposit so your partially covered, advertise asap and for whatever reason cancer or just plain moving, you'll have a vacant unit.You can charge the tenant for unpaid portion of the lease up until the date between the end of July and the end of Sept .. if you rent the apartment before sept 30th you have to adjust the move out statement and remove the days of unpaid rent you charged the moving tenant for, you simply can't charge double rent.You could say I'll retain security deposit and charge you  a early release FEE of like another /12 months or months rent.. if they agree and you re rent you do not have to pay back any days you filled the unit for which is easier to do.And yes you can get in a trial for cancer in a very short period.. my father was on a waiting list and had to either agree to move out of state for the period of treatment or be denied the opportunity to be included in the trial.. the person may find out at the last moment for this type of treatment.. my dad was on waiting list for quite awhile and when approved his treatment started within 10 days. ..

If refunds were considered to be so important with the COVID crisis, then why was AirBnB simultaneously denying claims made for cancelled reservations from trip cancellation insurance that THEY sold and profited from?   

lastly its hard to time the market but there is no denying when you enter and when you exit directly correlates with your success.The bigger issue I see as of today is the threads of Lenders pulling out of financing rentals either raising the bar or freezing all together..

I don't know how long this has been going on, but if there is no formal lot line agreement signed, I would deny any past verbal agreements existed should your neighbor try to use that as an argument if things escalate.

You can legally deny someone for something like not filling out an application completely, especially after specifically requesting them to completely fill it out.The same can be said for requiring people to read an ad completely and not contact you unless they believed they met all of your requirements, etc. 

PASS..... no reason given or find another reason..... you can already deny based on income.Don't overthink this...... don't start thinking about what "may have really happened" with the arrests etc..... not your concern.You guts is saying PASS.....don't go against that......

Either way it seems highly unethical to deny your client a legitimate offer because its not what the agent personally wants. 

I think it is "reasonable" to deny that request.

One of the things I added to my criteria, was that I denied people who were late to appointments (gave them a 15 minute window only, unless they called and had a good reason like they were stuck in gridlocked traffic), if they didn't call back when they said they would, or drop off documents when they said they would, etc.