Hi Paul and welcome to the forum,
Since you are buying in light bulk, that is going to be considered a wholesale deal, not drop-sopping of course. With wholesale, no matter if it's small or large volume, they are usually going to want you to prove that you are in fact a registered business before allowing you an account.
Of course you can check with them directly in regards to what info they want, but I've never seen a wholesale supplier sell to any unregistered business before, at least not at a true wholesale price. So my guess is that you'll have to take that next step of registering as a business if you want to move into the wholesale marketplace to trade.
Cheers