Barcelona B&B or boutique hotel for a great value?

My husband and I will be staying two nights in Barcelona for the first time in mid May. Our trip leading up to arriving in Barcelona will be spent staying in the homes of friends. I want to experience a warm and inviting stay without breaking the bank. I'm looking for recomendations of B&B, small hotel or AirBNB locations. I'm open to any areas in the city if they help me feel like I'm at home. ;) Thanks!