Amazing Location and comfortable rooms
Hotel Mayfair was in a perfect location for our 4 days in Paris - close to most locations by walking distance and right at the corner of Concord Metro station which serves for Metro Line 1.
The reservation staff followed up on our reservation as we had requested interconnecting rooms, and they were booked solid, and were concerned, but we emailed back, since we were traveling with infants and we would definitely need interconnecting rooms, they could not give us interconnecting rooms but did set us up in adjacent rooms, the only problem in this coordination was that the doors were squeaky and banged if let to close alone, we were worried about adjacent guests being irritated from the constant flow of traffic between the rooms or the occasional "Mommy he hit me...", but no complaints, so no harm done :)
Rooms were nice and clean, bathrooms spotless (but there was an issue with the shower we weren't able to get the cold water sorted out for two days - and quickly dipped through hot water until we were guided by the front desk for tap-coordination) - night desk was weak to support us for any issues and we were referred to the morning staff.
Loved the old elevator squeaky but a brilliant part of history, working condition and I hope they keep preserving this for posterity