I agree with h2o-ski. What's under the deck is multiples worse than what you're seeing above. That doesn't mean it'll fall apart on you soon. There were noticeable soft spots when walking before I bit the bullet & rebuilt yet she still performed great. Was a bit shocking once the underneath was exposed. I was able to set aside the stringers' fiberglass shells to use as a reference but the wood was just mush. Supra's design calls for notching the stringers at intersections allowing water to easily penetrate. It doesn't take much time or effort to improve some areas (adding limber holes for drainage, etc) as well as just doing a better job fiberglassing. Focus on those areas and new wood will last much longer than what the factory was putting out yet you still got 30+ years out of it (unless a PO already did some work). It's a big, dirty job but very rewarding.