Over the course of my adult life, I have had the occasion to rent property. I have always gotten a refund of my entire rental deposit almost every time (there was this one time...). There are a few things that we do to make certain that this happens. First, make sure that you clean the place regularly, this keeps down the need to scrub when moving out. Next, clean when moving out. Make sure that you wipe down all of the nooks and crannies. Clean the unexpected places, like the baseboards. Leave the place looking better than when you moved in. Most landlords want to turn the place over pretty quickly and the better that you can leave it, the more likely that they will have less to do when they re-rent it.
A little elbow grease, saves money!