If your deck is already constructed of lets say pressure treated wood. Then you should only have to stain, or oil it once. I plan on using a Thompsons clear water sealer after I finish power washing mine. You definitely do not want to paint a deck, unless of course you enjoy a variety of colors that you can mix and match along with your home. Paint generally requires much more maintenance and unlike staining one time only. You may be painting and scraping your deck every year to two years. Depending on the weather conditions.