looking for things to do in Florianopolis.. I would like to recommend you all the best place in florianopolis.
Its called Pousada villa tamarindo. Its not a youth hostel and couple will enjoy the place a lot mroe
In order to enjoy your stay in tamarindo, you should have a car or a motorbike. THey have amazing view,the best breakfast I have ever ate!
Its a bit expencive and not the commun travel budget accomodation but if you like to treat your self right

I would also like to recommend pousada 32, which is at a more popular beach called Barra da lagoa. Its just 32 meters from the beach. The place doesnt serve breakfast and is pretty simple, but if you are looking for quit place and straight access to the white sands, its the closest place to the water.