a) Books is vague. Commerce I is also very broad. He'll have a lot of different choices between a lot of different classes. Sure, there are the requireds like econ and comp sci, but he'll have a choice between psych, anthro, poli sci, etc. Catch my drift? You should wait till you at least know what courses you're enrolled in.
Which brings me to my next point:
b) You should wait till you know what courses you're enrolled in definitely AND which textbooks they are using definitely. Just because it SAYS required on the course outline, doesn't mean it is. Just because the prof INSISTS that you should get the latest edition $200 dollar edition, doesn't mean you can't get away with the 60% discounted previous edition.
On the flip side, there's no way to predict what book a prof is going to use this coming year. I'm pretty sure that shit is highly volatile.
3) For the love of all that is good and chocolatey, do NOT buy notes. Especially not first year notes. Here's why.
1) Confusing about something? Use your textbook? Not in there? Google it. Lemme repeat that. Google it. There's not a single thing you learn in first year that can't be found on the internet. And it probably explains it way better than any prof or student could.
2) Very rarely will you ever have to worry about having to write super fast in order not to miss any notes. I'm making up this number, but I'd say 90% of my classes have ALL had Powerpoint notes provided to us while we would take up the number examples in class (that's the jist of it). I think the exception was a first year history course I took and ECON 2X03 with Aswani, but that guy writes fuucking slow.
3) I forgot 3, I'm high.
Please just... tell him to breathe and shit. He has so much time to worry about this, and the last thing you want is to be unnecessarily losing out on money before you have to dish out your tuition.
Also, I read (after writing this) the part where it says you're in 4th year... Why couldn't you just tell him this? ;D