Forget space. There isn't a shopping cart out that needs more than 100MB. Getting 20GB isn't going to make any difference, since it will just be sitting unused.
I have dozens of shopping cart clients on 200MB accounts and have never had a problem. I guarantee to double the size if they get close. The server is set to tell them when they get to 80% and no one has ever gotten close.
Bandwidth is unlimited, so that is not a consideration. I guarantee my clients they will never run out of, or get billed for additional space, bandwidth, email accounts or anything else. Only restriction is the number of domains. One domain - $ 4.49 per month. 6 domains - $ 8.99 per month. 20 domains - $ 13.99 per month. With each plan, server space and bandwidth are guaranteed.
Avoid GoDaddy, their shopping cart is lousy. The only thing they have that's a good deal is their domain registration. The rest is over-priced and under-valued.
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