William's place is perfect if you're planning to live short term in Paris. Being set in the middle of the Marais, the location could really not be any better. You can walk into any direction and will be overwhelmed with the amount of options for brasseries and shops. Plenty of supermarkets are nearby as well. As a matter of fact, the first week of our stay we didn't even make it out of the neighborhood.
William's place has a good setup (strong wifi, a washer and comfortable bed) but it is quite small. I have hit my head into the staircase or ceiling on a number of occasions, but that was a price I was happy to pay to stay in the heart of the Marais.
Communication with William as well as checkin/out were great too!