Good size apartment and in a great location. Easy stroll to any of 3 metro stops but also a nice walking district and easy to get to places like the Picasso museum and Notre Dame before moving on to the other major attractions (if that's what you're after). Small supermarkets and boulangeries etc very nearby.
Good-sized bathroom and kitchen, with plenty of equipment etc. The two main bedrooms sleep 4 and the sofabed caters for another 2. So we didn't even use the single room (neither adult daughter were keen on the high bunk bed).
For those with younger kids, it's also an easy trip out to Eurodisney. Only took us 1 hour via the metro and was very simple but out and return.
Pre-stay communication was A1 as were check-in and check-out transitions. But overall a tremendous property for a family visit to Paris and one we would certainly recommend.