I spent a month there and i would highly recommend getting a guide there at least for the first few times you go. There are so many unseen hazards there that unless you already have some really good mountain skills, you definitely could end up having some problems with your route finding. Its a big burly place, i live in whistler now and as big as everything is here it honestly makes it just feel so safe in comparison. You probably would be fine if you did just go lap the vallons and the chancel, but there would still be some risks to an extent, and im sure you
dont want to limit the terrain you can ski. Not to mention your guide will show you so many awesome places there as well obviously. Your going to need avy gear as well, and you really should know how to use it as well. I owned my own so i cant speak on renting it, but im sure you can figure something out. Its an amazing place, i cant wait until the day i can get back there, but its a place that needs respect, so dont just go charging on in there until youre properly prepared