If you want a really unique experience in a 'platform' treehouse located in a "typical' low-middle income neighborhood of Seattle, this is the place for you. This is a lovely spot in a community home and garden. But there are some things you really should know before you commit to this experience:
The treehouse is completely open (to bugs, raccoons, and other potential visitors). It has no walls. We were told to keep all food away, or store it in the metal box provided. We only discovered the available mosquito netting after our second night. By then, we had gotten a number of mosquito and, especially, spider bites.
The treehouse is delightfully located amidst a grove of evergreen trees, which keeps it quite cool and diminishes the line of sight for privacy. But it does still feel very "exposed": it's right along a couple of neighbors' property lines, and one morning we were awoken early by a neighbor talking on the phone in her backyard.
The kitchen and bathroom in the small 2-bedroom house are available for your use. Both are well-used spaces, moderately clean, but must be shared with the host and her roommate.
The neighborhood does not inspire a lot of confidence. It's charming in its own way, but also appears to suffer from the same problems that most low-income communities do. We would not have felt comfortable walking there at night. We had a car and did not use public transit. The neighborhood is also right on the flight path for the local (small engine) airport, and just off the SeaTac airport path.
Long story short: you get what you pay for. If you need a budget place to stay, and you can roll with some of the funkiness of the setting, it can be a great experience. But I'd urge you to bring your bug spray and some earplugs!