Two verbs collide in this shape. 살다 is living — 없어도 살 수 있다, you can live without it, or you can cope with the heat because it is dry. 사다 is buying — 사고 싶어도 살 수 없다, you can't buy it however much you want to, and people will pay two hundred for it if it has the right logo. Only what is being talked about separates them; -어도 concedes the condition in both cases.