If a foam bed works for you, James’s place is an excellent base for exploring Seattle! It is exactly as described - a tiny house with everything you need, including full-sized range and dishwasher and a large shower. The fridge and washer/dryer are smaller, but workable.
There is a great bakery/coffee/breakfast spot steps away, and a number of interesting restaurants and bars (and two grocery stores) less than half a mile away. A nice level walk through a quiet, interesting neighborhood.
The No. 2 bus stop is very close by, and it will take you right to the city center. I found the public transit system to be extensive and pretty easy to use. I downloaded their Trip Planner app and although it doesn’t have great reviews it worked well for me in telling me how to get from where I was to where I wanted to go.