Like, all you really need to build a settlement is water, electricity and a source of carbon.

That’s not all you need. You also need breathable air and surface pressure that isn’t going to make your eyes pop out of your skull. You need protection from too high levels of radiation.

You’re not living on the surface of Mars. That environment is not survivable. If you’re going to Mars, you’re living underground or in enclosed habitats. You can do that here. Go get a little bit of land here on Earth and build a self sustaining enclosed habitat and live in it. It would be a lot easier and cheaper.