Groundfloor to expand near the beach

ground floor in refurbishment, close to the beach, there is the possibility to build two more floors, at the moment the house only has a ground floor, a garage and two bathrooms, in front of the house we have a terrace of 24 m2 and we have a patio of 16 m2. the owners started to reform it, so it has two new bathrooms, the kitchen is unfinished and the project to put one or two more floors is still missing. the house has 6.9 meters of frontage on a plot of 176 m2. in front we have the living room, and two rooms. at the back we have the interior patio, what will have to be the kitchen, two bathrooms and facing the other street the garage.