I just returned from staying in a Cobblestone apartment in Le Marais. Our accommodation was clean and cutely decorated, the bed comfortable, and the neighborhood lively. We really enjoyed our stay.
My traveling companion rented from them in 2019 and there have been changes from that time that were not updated on the Cobblestone website (at least, at the time we booked). The information book in the apartment hadn't been updated when we arrived either.
So, just for your information:
1) Apartments you might have stayed at before 2020 may no longer be available. We booked one apartment in 10/22, but were told in January that they were no longer managing that location and given a few alternative locations to choose from.
2) Car service is no longer available. When my friend went in 2019, Cobblestone had a specific car service you could book. Now, they will just tell you to use Uber or a taxi.
3) Photography sessions are no longer available. This was a little bit of a kerfuffle for us because when I asked closer to our travel dates about scheduling with a photographer, they said they no longer offered the service. I had to point out that we had prepaid for it at the time of booking. They apparently completely missed that they still had outstanding orders for the photography add-on. It then took me three tries to get a refund. They kept saying they had refunded me, but it wasn't until the last day of the trip when I asked for documentation so I could take it to the bank when I returned to the States that the refund was finally issued.
I would definitely still stay at a Cobblestone location again, but adjust my expectations a bit for how things are post-Covid. Hope this information is useful!