Great Boutique Hotel - Make sure you get a high floor
The Monaco is everything a boutique hotel should be. Excellent amenities, all the fine touches. Great staff. 
You will not be disappointed with your stay here, but you need to know two things...
1. Hotel WiFi is crazy expensive. Not to worry. Go out the front door, turn left, walk 10 feet (literally) and there is the nicest Starbucks I have ever seen that will give you all the free WiFi you want.
2. The lower floors are subject to street noise. I stayed on the 7th (out of 8 floors) and slept like a lamb. As soon as you get your reservation I recommend you pick-up a phone, call the front desk ((206) 621-1770) and have them set aside a room on the highest floor you can get.