Must have /out/ tools?

What are some items that you swear by? I'd like to only have to buy things once for a lifetime.

Finally starting my cabin in the woods. I know I will need a lot of stuff, (chainsaws, drills, atv) and some of it I will have never heard of. Any warnings are appreciated since I really don't know what im doing. This would be in canada, ontario or alberta most likely.