The best part about this listing is clearly the location. It's perfect. If you want to stay in Le Marais, there is likely not a better place to do so. The block itself is very very quiet, as it's hidden behind a private gate. But at the same time, you're right smack in the middle of Le Marais. Full of bars and restaurants and cool shopping.
The only real drawback is that the apartment is small, and also one of the bathrooms does not have a toilet. This can be a big deal if you have more than a few people. At the same time, the hot water runs out in the shower in under two minutes.
You also pay extra for basic supplies like soap, etc.
Overall great, just be very aware of the 1 toilet and 2 min showers.