When you purchase a new home, what is one of the very first things you do? You paint the walls! We think of the garage as an extension of the house. And there is nothing that can make a garage look more finished than painted walls. White is boring and shows dirt more than any other color. So lets fix this right now.
Other Options to give a more finished look are adding base trim or crown moulding. This gives the garage the same look as the interior of your home.