I've lived in my fair share of apartments over the years and I always enjoy the little added touch of a creative move in gift on the day I get my keys. Usually these gifts are very utilitarian, laundry detergent, dishwashing soap, a trash bag, etc. I ran across some adorable free printable greeting cards that Canon is offering. I think it would be fun to have a few (10 maybe) "I've Moved" cards waiting for a new resident to send to their friends and family.
Here are Moving cards from Canon:
A few Just Moved cards may also make for a fun addition to your new move packet you give when someone signs their lease. You could also have your designers create a custom card specific to your property or there are any number of sites that offer cute Just Moved graphics.