For any of you who are planning on writing a web-based shopping cart tool, here are two basic tips to keep in mind:
When giving a shipping estimate, asking for state and zip code is redundant. It’s okay to have both fields, but if someone (like me) puts in the zip code, don’t give an error saying that you also need the state. Because you don’t. And be absolutely sure not to just return the user to the page without giving any sort of error at all.
When someone clicks “Add to Cart”, without entering a quantity, you can safely assume that the quantity is 1. An alert box saying “The following errors were found: — please enter a valid quantity before you add this item to the shopping cart” is something of a turn-off.
Bonus point:
People considering buying something off of a web site generally want to know what the item costs. Most web sites, if they include pricing information but don’t have free shipping, don’t actually tell you what the item really costs until you get 75% of the way through the buying process. You get bonus points for having the total cost right on the page with the item’s description.
Just ask for the shipping zip code, and provide a link for internationals or fancy shipping. Store said zip code in a cookie, and always display the ground rate on the page, giving the potential customer the option to view different rates using some sort of clickable popup.
