We had a great stay at this appartment. Pénélope the host was so flexible that she let us leave our luggage some hours after check out because the next person would have a late check in. That gave us some hours more to enjoy Paris. We would have understood when that wouldn't have been possible because of cleaning or check in of the next person, but the offer of Pénélope saved us taking the luggage in the middle of a heavy rain to some lockers. Thank you very much dear Pénélope.
The instructions for check in were very detailed and we didn't have any problem.
The appartment is a jewel, in the heart of Paris, near to 3 Metro Stations, that saved us a lot of time. I completely recommend staying here, your should book in advance to find this place free on the dates you want.