Also everything is more expensive because it's so remote. There are no roads so everything has to be brought here by airplane or boat. If you order something from Amazon (the website) to the Amazon (the rainforest) shipping is at quite expensive and then there's import fees too...
If they need/want more than just lighting, then fair enough. But for just lighting, rektide's proposal blows a generator out of the water.
Yet. It's daunting to me to imagine replacing well known infrastructure with something custom & different. You could try to get a bunch of automotive 12 & 24 lights but there won't be great fixtures. You also need 12v versions of most appliances; fans, fridges, others.
Your upgrade capabilities also seem limited. If grid power does come, you might be stuck with a bunch of abornal choices. Your wire loss is much much higher with 1/10th the voltage or 10x the amps per wire, which limits scaling out on DC, is a counter-inefficiency that grows the bigger your system gets.
I think it's a good idea. Personally if I built a small off grid home or RV I'd probably do 48vdc. But it'd be much more work & require a ton of expertise.
I guess what is needed to run lights would be a solar panel, a battery and an MPPT controller.