The location of the apartment is ideal - convenient to night life and the metro and close to Ile de la Cite and Ile de Saint-Louis. But there are issues.
The bedroom gets no airflow and was hot even when the temperature was in the 50s outside and the windows were open. Beware in the summer. From the listing, should not have been a problem because of the air conditioning, but the units did not work.
This showed us another problem - the hosts. They wrote that there was a local contact for issues, so when we returned from dinner and learned the a/c did not work, we emailed the hosts to ask if they wanted to call the local contact or have us do so directly in order to get instructions for how to turn on the air conditioning. It was around 1030pm, and they promptly responded that we could get no assistance at that hour. The tone of their message was horrible, as they told us "in case you didn't knew, in France slavery was abolished a while ago."
The next day, a portable air conditioner was brought into the apartment because the air conditioners did not work, but the bedroom remained quite warm.
This lack of responsiveness for basic needs was not an isolated problem. We also contacted the hosts to tell them that the shower was not usable (clogged drain). Of course that can happen, but they did not fix it the next day. It took until two days after we asked for assistance before the shower was usable.
There are other things, such as having blankets without duvet covers and pillows that were too big for theirs cases that looked like they were well past due for replacement. The toilet seat was broken. The pot to boil water did not look like one would want to drink from it.
If the apartment were priced at bargain rates, i could see these things needing to be tolerated. But not at this price range. And nastiness is not acceptable at any price.
Because of the great location, a one-star rating seemed unfair.