Because of the distance between the two outdoor speakers, I would set the Sonos Amp to Dual Mono mode to send a mono signal to each speaker.

The den and kitchen space is large enough for four in-ceiling speakers (two in each room). Depending on where the two speakers in the den are placed, you could potentially use them as rear surrounds with a Sonos sound bar like an Arc or Beam (Gen 2).

One speaker in the office and bar should be fine. You might consider using a dual tweeter stereo speaker in each room like this:

https://www.crutchfield.com/S-eB1nU86yTV1/p_735DT65STR/Definitive-Technology-DT6-5STR.html

Have you considered using any other Sonos speakers like a One, Five, or a stereo pair of Ones in the office or bar rather than in-ceiling speakers?

Thanks so much, really appreciate the help. A few follow ups:

• What do you think of the speaker locations in the ceiling? Asking in terms of spacing relative to the rest of the room and if those are the right parts of the ceiling to put them. For the Bar and Office I don’t think it can go in the middle of the room as pictured as there is a light there. Should they in the bottom right corners or somewhere else?
• The dual tweeter stereo speaker you included wouldn’t work with Sonos though since it’s not their product right?
• I hadn’t considered a One or Five in the bar or office rather than in-ceiling speakers, but do you think I should? It’s definitely cheaper but not sure what would be the best

Thanks!

AMP will support any 4 or 8-Ohm passive speaker. The  dual speaker (sometimes called “single point stereo speaker”) should be wired as a left-right pair. AMP will think that this is a pair of speakers. The SONOS speakers are regular passive speakers with an added feature that allows AMP to recognize them.

Can you connect as little as 1 speaker to an amp or up to 3?

Also, any recommendations on good quality 4 or 8-ohm passive speakers?

I would set these up in pairs, either 1 or 2 pairs, depending on need.  For the cases where you only want 1 speaker for an area, or a pair of speakers and single speaker (3), I would use a dual/stereo speaker.    

The architectural speakers that Sonos sells are very good, and you actually use 3 pair with these, but I personally feel they are overpriced.  That vast majority of speakers are 8 ohm.  I geherally use polk speakers but there are lots of good options out there.

Thanks. What are some recommendations of speakers that are good quality with decent low end that are less expensive than the Sonos ones?