Stick with 24v for the "big" stuff (inverter, pumps, solar, etc) as they're more efficient, then use a 24->12v dropdown converter for lights / chargers or whatever else can only run on 12v. Double check your fridge as a lot can run on 12 or 24v DC.
We're electric only with reverse cycle air conditioner, electric HWS, etc so it is doable.
The reverse cycle AC is efficient for heating (2.5kW of heating using just 450W of electricity) however you need to make sure you're well insulated to reduce the run time. We have a 35mm thick 80kg/m3 PU foam box and dual pane windows which helps massively.
Hot water uses ~750Wh to heat our 24L tank which is pretty easy to do on a moderately sized power system.
Induction cooking using single hotplates is great because they don't take up any bench space and you can use them inside, outside or 30m away if your extension lead is long enough. A couple of steaks uses ~250Wh
We use a pressure cooker / slow cooker a lot too, the pressure cooker uses ~500Wh to cook a stew/curry in about 20 minutes. The slow cooker is great for ribs, I usually do them for 8 hours using about 1000Wh
To run all of that we have 1600W of solar, 300Ah @ 24v of Lithium, and a 130A @ 28v alternator for when the sun isn't shining. We've done just over 12 months full time travel now without needing to plug in.
We looked at Efoy but they're just not big enough to be useful - eg. their biggest model produces just ~2500Wh in a 24 hour day. Fast-idling or driving produces ~3500W every hour. Our solar produces ~6000Wh on an average day and on good days over 10000Wh.
We'd need 2 of them running 24/7 using 150 litres/month.. The Eofy doesn't make sense for large consumers of power.
