If you do your hosting through DoDaddy, and get their Deluxe Package, you can host as many sites as you want in the space allowed for under $10. They have a sliding scale based on other services you select (such as domains) and length of time you lock in. In addition, they offer built-in blogging and free shopping carts using OSCommerce or ZenCarts. You need to be a bit web savvy to use these carts. If this is more than you want to deal with, you can use their shopping cart package for around $10/month. It links seamlessly with PayPal or you own online merchant account. It is quick and easy to set up.
I find the GoDaddy website a bit confusing to navigate, but if you call Tech Support they are GREAT and walk you through everything and/or set you up themselves if necessary. I must say they have the friendliest tech support I have found.
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