No problem with getting plugs, motor oil or gear oil, just make sure you get the right stuff for marine application. You might want to look into buying cheap auto filters for your boat though. I have heard more than once(not sure it's true) marine oil filters are a little different, they allow for more flow and pressure than an auto. You don't run your car constantly at 4200rpms like you do with your outboard. For a couple extra bucks once a year I'll stick with my Honda marine filter. BTW the Honda blocks on the outboards are the same as depending on HP, Accord/CRV/Odyssey/Element/TSX engine/Ridgeline/Inspire/MDX/RL/TL. But the numbers for the oil filters are not the same..While your at the auto part store get your 4 stroke oil filters , oil, and your 90 wheight lower unit oil. Its the same stuff. Yamaha does not have a factory that makes $20 oil filters. They are buying them from FRAM or some other major manufacturer. I get everything at Walmart.