Well, you might want to think about cash. The most effective way to do it is a rent reduction going forward. Oddly enough, that is even more popular than a stack of dollars, according to a survey cited in an article by Chris Clothier.
|This picture seems particularly appropriate.|
It's important to remember that you want to minimize turnover as much as possible. It's also important to remember that, after your good tenant moves out, you might get one like this.
Since I have a lease coming up soon, this information is particularly timely for me.