Where are the best places in Florence to sit with coffee and people watch in the evening?

I wouldn't stay/sleep anywhere close to the Duomo or Piazza Santo Spirito as both are very noisy at night.
However, both are great to sit with a drink in the evening and people watch!
Florence is easy to walk around in, and the centre is really quite small compared to other cities.
I would just choose to stay a little bit away from the main touristed areas if you want to get any rest.

Thank you for the advice !

Several years ago we stayed at the 4 star Hotel Albani Firenze on Via Fiume. It is located a few streets from the train station, very close to Via Nazionale, and a 10 minute walk to the Duomo and Piazza Del Signore. The property is extremely clean, the staff is outstanding, and the price was right. Additionally, the hotel is in a very quiet neighborhood.

One evening activity we like is sitting around the Uffizi at night listening to the street musicians and people watching. One drawback is that you must sit on a wall or steps. The cafes are on the other side of the piazzas. A number of the musicians are very talented and their music is quite good.

Buon viaggio,

One evening activity we like is sitting around the Uffizi at night
listening to the street musicians and people watching. One drawback is
that you must sit on a wall or steps. The cafes are on the other side
of the piazzas. A number of the musicians are very talented and their
music is quite good.

I'll second that. First trip to Florence in 2010, got a gelato and heard a solitary flautist playing songs like the theme from Beauty and the Beast in the small street in front of the Uffizi. With the natural reverb against the buildings, it sounded magical and why we came to Italy.

We've stayed at the Tourist House Ghiiberti, a b&b, a couple of times and I'll definitely return the next time I'm in Florence. It's on a small street behind the Duomo, in an industrial building. The name is because the building was supposedly Ghiberti's workshop. It's run by a couple who have decorated rooms with their mosaics; rooms are very comfortable, and it's close to the center. Even has a PC in each room and free Wi-Fi and internet.

As for sitting in the evening, and Aperol spritz on the Piazza della Signoria does it for me!

I agree with sitting on the steps by the Uffizi or Ponte Vecchio at night for sun set and music, BYOB(W). Several years ago we were at the Ponte Vecchio for sunset and someone was playing the "Theme from Romeo and Juliet" on guitar-priceless!

thanks.. We will for sure do what you guys did.