I stayed, together with my girlfriend, in Roberta and Stefano's apartment one week in July this year (2013). It was an excellent experience! Excellent because of the very high standard of the apartment, the location (it is central, not just "close to the centre" but actually right in the very middle of Florence), the size and layout. Roberta and Stefano are truly kind people, warm, attentive and eager to make your time staying in their apartment an exceptional experience. Thank you guys!