I would highly recommend Billy's place for your trip to Denver! My husband and I spent 5 nights at his home with our 18 month old and it was the perfect amount of space. This might be a little tight for two couples but definitely doable, and the living space and backyard are very spacious. We loved being able to walk to the playground and museum in City Park, and you're just a few blocks from a coffee shop, great breakfast spots, and the grocery store on Colfax. Billy is a great host and proactive communicator, making for a seamless process.