My 1-bedroom apartment with a huge 33 sqm terrace is in the center of Nice, on the Promenade des Anglais (beach view). My dog is 16 years old, blind and arthritic. She gets 4 walks a day but not very far--usually 5 minutes suffices. She is easy to care for, as she sleeps most of the time. She has a dog buggy so you can take her along on walks if you wish.
Nice at Christmas time has many activities. The weather is usually mild.