Start in LA, rent a car, drive up the coastal highway to north of SanFran, CA (5hrs), then to Portland, Oregon(8hrs), then Seattle, Washington(2hrs), then Bellingham, Washington(1hr), then if you want check it out you can cross over to Vancouver. Or head back to Seattle to fly home. Would be a very casual 3 day drive with limitless scenic views. Stay in the cities for a day or two per time allowed. Arguably the prettiest 'drive' in the country.