Like anything, you can spend a crazy amount of money on a
Concert Guitar..
A Cadet size is comfortable and still has a 650mm scale length..
I'd stick with a cheap model and always keep it for practicing.. I actually put old shirts inside the guitar so it isn't so loud as to not disturb anyone.
Expensive guitars are louder. Cedar Tops are warmer and Spruce is brighter. I've never owned a Spruce tho..
Check out the crazy prices on this website..
https://www.classicguitar.com/