The van (aka La Furgo) has already 2 years with us. Since then, we did around 30k kms and the inside evolved quite a lot. Zooming in into the electrics, La Furgo came with a second (lead) battery and a splitter, that was feeding a heater and that's it. As we could see, it took a night for the heater to leave the battery quite empty and the splitter needed quite a lot of kms to fill it back enough for a next night.