My suggestion about your apartment renovation consists of a living room, a full equipped kitchenette, 3 bedrooms and 2 bathrooms, trying to follow the wishlist that you set as much as possible.
The layout of the different rooms provide a lot of storage space. At the same time, I believe that the passage through the different spaces of the apartment should be comfortable so that your accommodation can be functional and pleasant.
Regarding the floor material, since the apartment is near the sea, my suggestion is to use a rough material and not slippery, for safety reasons. So, I would kindly suggest to use stone tiles in a bright color to help the natural light diffuse through the entire apartment.
Regarding the living room, I kept in mind that you would like to use a bed-couch. So, if you turn the dining table 90°, there is enough space (more than 2 meters), for the couch to be transformed into a bed.
Regarding the color palette, I kept in mind that you would like a cheerful environment, so I would suggest to keep the walls in white color and then to add some color details in turquoise and pastel peach, just to capture the beach ambiance.
