Are any of these locations already wired for electricity or sound?
@DigitalDawn is a distributor for a number of brands and is awesome to work with. Triad is her main speaker brand I believe and they have a couple straightforward speaker designs for outdoor applications. FWIW Triad builds all their speakers in Oregon. I would go for speakers mounted on the posts as in ceiling designs tend to have that 'voice from above' effect.
You'll want to have a location for the amps and electronics to be indoors tho. Streaming is easy and if you don't have a good Wifi connection at your desired listening locations, I'm sure there are routers for this type of application that you can hide up in the ceiling of the carport, for example.
Make no mistake tho, internet is great when its wireless, speakers ARE NOT. If you are not already wired at these locations, you will need a contractor that understands how to wire electricity and speakers, separately.