I only need my wand. It takes care of everything else.

Otherwise, my dog, (whom I should have named "Dobby", but Dobby only appeared later), A niobium alloy magnet, and a length of hosepipe.

Well, My dog is the best company I could hope for, doesn't nag and defends me to his utmost. My magnet not only points north, but strikes sparks when struck against rock. And the hosepipe would enable me to hide underwater if I needed to, and to collect food from the ocean without having to hold my breath for too long. It would also double as a rope. If I got fed up, I could turn it into a musical instrument too, and my dog would sing along.