I have stayed at Marc's place a couple times now on work trips to Geneva. It's everything I need -- a comfortable space with easy access to public transportation and places to eat. The location is excellent if you want a quiet neighborhood scene in old town, with cafe's and quiet restaurants. The lake is a five minute walk down the hill. You can walk to the central train station in about 20 minutes. Marc is quick to respond and makes checking in and out as easy as possible.
A helpful hint for the shower if you stay here: The shower's water pressure is REALLY good. There is so much water pressure that you will not want to turn the water on all the way. Turn the water on slowly, and make sure that the shower head is pointed straight down into the tub. Otherwise you are likely to suddenly spray water into the bathroom.