I would opt with air bnb or checkout Hotwire, I rented some amazing rooms for very cheap under 50 a night. Summer time is almost certainly too hot to skate in the day, the humidity is awful. Barcelona has more spots than the entire us, so finding them are easy the skahateyou site is a great tool. Remember the grocery stores are super cheap to get food and beer and if you are wanting to eat out I suggest bodabee sandwiches near the main post office, also by a very famous bank spot.