It would be awesome if this company would provide a parking location, such as a lot or garage nearby the closest pickup locations instead of hotels, as I am not staying at any on the list, nor in Portland.
When I called the Tripadvisor assistance line, they supposedly called the company and found out that I could park at Shilo Inn Rose Garden for free. I then called Shilo Inn, and they informed me they charge their guests for parking, so no, parking is not available for a tour company guest. I had wanted to do this specific tour, but unfortunately, this forced me to choose elsewhere.