New to Sonos and need advice for a large loft surround sound

I am not new to home theater, but I am new to Sonos.  We having a custom build started and I will be meeting with the low voltage supplier in a couple of weeks and I am trying to see what Sonos system would work for my needs.  In the loft upstairs (22’x18’), we will have a TV on one wall and a sofa on the opposite wall.  What Sonos system would work best for that room?  We are also thinking about having a few other Sonos speakers around the house so I want to know what’s a good setup to have Airplay2 added in the system as well.  Thanks in advance!