Johnny Bar

So i have bren planning on building an earthship for some time. But now that I have seen my property in person i noticed that my soil is mainly just sand. Is it possible to fill the tires with sand? If not what type of natural building would you recommend?

What brand and type of electric engine would you use for an electric motorcycle, car or tractor and why?

So I currently live in the Pacific Northwest. I have lived here most of my life so I know this climate pretty well. But I am moving to Guyana. I have never lived in a tropical rain forest before and was wondering what sort of plants and trees grow best to support a great ecosystem? What sort of plants do I want to grow to chop and drop to raise quality of soil? What can I do for flooding in the rain season?

Also any books or Internet links would be greatly appreciated.