Overview: This apartment in the Marais district is in a great location near shops, restaurants, and two Metro stations, but is not very well maintained.
First - the great parts.
Just a few steps to the Place des Vosges, with two little grocery stores across the street, and cute shops, several museums, restaurants and cafes nearby, this place is in a great, safe location. It's also close to two Metro stations on different lines so it's easy to get to lots of different parts of the city. Easy walk (20 minutes) to Notre Dame and Ile St Louis, Ile de la Cite.
And as advertised, the apartment is in an old, historic building with huge tall ceilings and cool exposed beams. Plenty of space and at least one of the beds was very comfortable. The other was moderately comfortable. The towel heater in the bathroom was fantastic.
Now - the not-so-great parts.
Even for an old city apartment (ie, I wasn't expecting a pristine, shiny, new place) this place was not very well maintained. The refrigerator did not work at all and when I asked the landlord he told me, "It's not really my fridge... look on the back for a button to see if you have to push something." So, no milk in the fridge for coffee or saving any leftovers for us. Several of the lights did not work and some of the fixtures didn't even have bulbs or were dangling by wires. The bathroom shower ceiling was very low and mildewed (probably from the handheld shower hitting it all the time) which was kind of icky for my tall son.
Also, we were there in February during a cold spell and the heaters in the apartment simply were not sufficient to keep the place warm. For the first two days we had to sit right in front of the heater to stay warm - so we didn't want to hang out there at all. Fortunately, the bedcovers were cozy enough to keep us warm while sleeping.
RECAP: Nice enough in warm months if you aren't looking for a pristine condition spot. Good location for safety and mobility.