Galleria dell'Accademia, National Museum of Bargello, Medici Chapel, Michelangelo's Secret Room and Orsanmichele all are open Tuesday to Sunday from 8:15AM to 6:50PM (last entrance at 6:20PM).
They are closed every Monday, January 1 and December 25.
Palazzo Davanzati is open Tuesday to Thursday from 8:15AM to 1:50PM (last entrance at 1:10PM); and Friday to Sunday from 8:15AM to 6:50PM (last entrance at 6:10PM)
And is closed every Monday, the 1st, third and fifth Sunday of the month.