They responded and said they appreciated the gesture but were now going to go back and talk to the group and see if she really does want to cancel or not.  

First, I want to let him know that I truly appreciate the lead, and second, I want to continue to build our relationship in hopes of receiving similar leads in the future.So, real estate agents, what are your favorite, best, etc. gifts, gestures, that you have received from investors as appreciation for your work on a deal?

At least a gesture that says it's a bad situation for everyone." and my response was: "If you had brought up the issue in a serious way, I would have fixed it.

without knowing anything about your landlord/tenant laws, this is what I think...they pay for a whole month. if a tenant decides to move out in the middle of a month, you wouldn't refund half the rent. same should apply here. that being said, typically you are not allowed to earn double rent so if a tenant left halfway through and you re-rented immediately you would then have to refund original tenant.you are now taking rental off the market, so in my opinion the right thing to do would be to refund for any days you occupy, same as if a new tenant were taking over. if you move in on 15th, refund 1/2 if you move in on 20th refund 1/3, etc. that's my moral assumption, and is not based on your local laws and is not intended to be taken as legal advice.now...if you wanna be a nice guy you can refund half the tenants rent for the month in light of the fact that you are forcing them to uproot their lives, and thank your lucky stars you are not in a state that requires you to pay moving expenses when owner occupying...this is purely a good will gesture though and has no business value

I agree with the posters above that a $50 gesture will go a long way to let them know you're looking out for them.

As a gesture of goodwill, you can prorate the rent and pay him a nominal amount for the days you have stayed there, if he even takes it.Hope this helps.

However, you can offer some kind of food reimbursement as a good faith gesture.

I was going to do before and after shots, but felt those trying to eat their breakfast might not appreciate the gesture

I'd also state that this is a good faith gesture only. 

Than a gift is a great way to let them know you appreciate them.I try to find out the favorite food that your manager likes to go out and eat and give them $25-$50 gift certificate for it.They will always take care of you for that gesture!