FANTASTIC LOCATION! Right on the Metro line, easy access to all major attractions.
CHECK IN IS CONFUSING. Here's what you need to know. The address will take you to a big red door underneath the street number provided. This is NOT the correct door. It's actually the wrought iron door about 15 meters to the right of the red door. There's a four-digit code for this door that will be provided. The unit is the first one on the right and there is a lockbox on the door they will provide a separate code for. Get through this and you're set.
APARTMENT IS NICE. But the furnishings are a bit tattered. There is a washing machine, but no dryer. Main bed is a pull out sofa bed, but it is surprisingly comfortable and I slept well on it. Small kitchen with stove, fridge and microwave. Wifi is free, the password will be provided.
Overall, this was a very nice apartment experience in the heart of Paris, and I would recommend it. Just make sure you note the check-in instructions above.