[Originally posted by AZBuck]
Welcome aboard the RoadTrip America forums!
You actually seem better informed about what's available to you than most Americans setting out on such a trip!. To fill yourselves in on some of the details of what's in that general neck of the woods, have a look at some of these previous discussions of similar trips. As for accommodations, by September things will be getting pretty quiet in the Pacific Northwest as fall settles in, things start to get cooler, and the kids have to be back in school. That means both that there should be plenty of vacancies and that rates will be starting to drop, so I don't think that you should have any problems finding places on the fly. Also, pacing can be left to you're own whims. 10 days is plenty of time to get from Seattle to San Francisco. I would just suggest that you plan on getting to San Francisco a couple of days before your flight leaves so that you'll have time to see some of its sights and not be rushed at the end to make the plane home.