I don’t really care about voice control - I’d typically be using Spotify through the Sonos App, BUT…

it has to be able to connect to a bluetooth capable turntable!

Any Sonos speaker can be grouped with any other speaker in a multi-room setup, to play synchronised sound across the speaker mix. If you want a stereo pair in one room, the speakers need to be the same - although a One and One SL are considered the same. 
 

For portable/outdoor use, the Move is your friend. 

He kind of skipped the Bluetooth question. The only speaker that Sonos makes that has Bluetooth built in is the Sonos Move, but when used in tat mode, it is not part of the Sonos ecosystem. In order to connect your Bluetooth turntable, you’d need a Sonos with an analog line in, to which you would either connect a Bluetooth receiver or the pre-amped signal from the turntable directly. There is no way to use Bluetooth to send a signal directly in to the Sonos ecosystem.

Sonos is still the best at multiroom, but an all Sonos set up can get expensive very fast, and there are now many cheaper approaches if you know exactly what your build is meant to do.

The first thing to know is why multi room? What exactly do you mean by that? How often do you move from room to room and need the same music to be playing in each room as you do that? Is this a permanent need across rooms or will you often be changing the rooms that are grouped together?

Kumar,

I guess I just want a seamless listening experience, as much as possible, as my budget allows. So I wanted to start with a manufacturer that I could build elements into. The rooms probably wouldn’t change much (my house is pretty small), but I would hope that eventually I could roam a bit without sacrificing my musical “milieu.” Though perhaps, as you say, it might be better to go with a cheaper system for now knowing that eventually I’d probably do a Sonos 5 with an analog line in, pre-amped turntable, with a One and a couple scattered SL Ones, then add a Move for outside.  All of this is eventual… no way I could afford that now. :-)

So i’ll probably end up doing a cheaper blue tooth set up for now while I save up for a Five. Maybe cheaper Sonos alternatives will pop up in the mean time?

There are cheaper alternatives that work just as well as Sonos does, today. But they won’t give you as easy a way to “roaming around without sacrificing my milieu”. So if that feature is really important to you, start with a Sonos 5 that allows a turntable to be wired to it. 

Till then, one of the very cheap speakers like a JBL flip 3 may suffice, to get better sound from your phone via BT. The superseded model is still good and better value now that there is a flip 5 out.