I am going with a multi-layered approach
220V for Oven, Hob, Electric heaters/ roof A/C
120V for microwave, dishwasher
24V for solar transfer efficiency
12V , just because ??
5V USB- charging phones, etc.
As usual, I am coming from the military angle. They employ 24 V systems for majority of their systems. You can get many accessories that are extremely
well-built & quiet for reasonable in surplus. Impact guns to ventilation fans to lighting to fuel pumps. Packard connections rule here.
I use the PSWNV720 Pyle step-downs for the 12V supply- 85 % efficiency, .2 amp no-load draw, so a few rocker switches to kill when not in use help. $37/ebay delivered
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Many LED lights are rated up to 30V, so no need to convert from the 24V.
USB DC/DC 12V to 5V 3A 15W Dual Female Panel Mount USB Step Down Module L1I9 $4/delivered from China, again, rocker switch when not in use.
DC motors are voltage dependent, so a 24V DC motor just spins slower at 12V.