If you are a new business one of your first big headaches is setting up a system to keep track of your inventory. The first step is usually to create a system of Shop Keeping Units (SKU's). It's a difficult and time consuming process.
When we first looked into using a shopping cart system to sell our collectible and surplus "stuff" the requirement for an SKU was a major reason it never got done. What finally sank in was that since each item has it's own page in our online stores, the URL of that page is in effect and SKU.
The PayPal Buy Now button/system we use to collect money from customers sends the URL to PayPal and it is included in the email we get when PayPal notifies us the payment was made. All we have to do is go to that URL to see what they bought.
Works like a charm for what we do.
We have one site dedicated to the sale of rose pictures. Clicking that link will open a new window where you can see how our digital sales sites are designed. The core logic of each is the same but the header image, photos and text are unique to each site.
We find that building small sites around many long tail keyword domains brings in organic traffic which would not find us otherwise. It's something of a chore to keep track of the sites, but worth it in our opinion.
The PayPal button actually works across sites; if you select a rose picture on this site and then go to our Windmill Pictures site and select another one, they will both show up in the buyers shopping cart and can be purchased with a single payment.
In the future we plan to add Google's site search to these sites which will make it easier for potential buyers to see if we have the picture(s) they are looking for.