We had a very late checking and early departure, but the owner made this very easy with good communications and key safe.
The nearby beach is great and very clean. The are a few places to eat nearby, but you'll gave to go into La Baule and further afield for any thing gastronomic.
I'd mention 2 things that didn't ruin or holiday, but would like to have known sooner. There is no wifi in the flat, though there is a limited service in the hotel area. While the building has air conditioning, the flat does not, but if you open the small window in the main bedroom before about 11pm it will drone constantly. That said we were there in 24-32C and the heat wasn't an issue (for a family of redheads).
The kitchen was well equipped generally (apart from a good sharp knife), with induction hobs, a microwave and a good fridge.
We'd recommend the area as family friendly, if not particularly gourmet.