I considered using 24V for my living room lighting, but availability is an issue. The much more common 12V works fine as long as you consider the wire gauge you

I considered using 24V for my living room lighting, but availability is an issue. The much more common 12V works fine as long as you consider the wire gauge you need to prevent the voltage from dropping too much. For example, if you use RGBWW strips (i.e., four channels; RGB plus warm-white, as you rightly recommend), you could have one -12V lead shared with a thickness of 4mm², and four separate 12V leads at 1.5mm². At around 4.2m distance (at the farthest) I measured an acceptable voltage drop of 3.9% for 405 SMD5050 RGBWW LEDs. But yeah, you do need to consider the wire gauge of your cabling, depending on the number of LEDs driven.