I just purchased a used Hyperlite snowboard with boots and the bindings.?

This is the wrong forum. Look at the Boots forum.

To answer your question though, most manufacturers will tell you what sizes the bindings are made to handle. Some of the more fancy boots actually have a sole that's supposed to reduce the size (i.e. it's an 11.5 that fits like a 10.5 in the bindings).
I'd feel safe buying just about anything online EXCEPT for boots...

tl;dr:
BUY BOOTS IN PERSON AT A STORE AFTER YOU TRIED THEM ON AND DECIDED YOU WILL LOVE THEM FOREVER AND EVER

Do you think this was a good deal for $100.00. I know the person I bought them from and the reason he sold them was beacause he was getting a divorce. I know for a fact he only used them once.