We stayed for one month at Alexandre's place, most of it during lockdown - and we had a great time. The flat is very spacious and really enjoyable - as the flat & kitchen are well equipped.
The living area is very bright and gets a lot of sunlight, which makes being stuck inside a bit better.
The flat is located in Saint Martin, which might not be the most fashionable area of Biarritz but is very quiet while being really close to the city center, Bibi and the beach - with all the restaurants and Les Halles.