I am shopping for a 5th wheel. The one that looks good has a little whiff of "eau de sewer" inside of it. This rig has been stored outside in the Arizona desert heat for two years (without being used). Am I right in thinking that any odor whatsoever should have been baked out by now?! There is no obvious flaws, (no obvious petrified doo-doo). So what do you think? Should I keep shopping? If the odor is somehow imbued in the tank, can I clorox it out? Help!