You should consider Shopify, Etsy, or even something like Ebay or Amazon. There's absolutely no reason to reinvent the wheel here. Ecommerce can be a real can of worms.
Hi, dvt. Thank you for your answer! I should have clarified that this for now it's a low-scale project in a country where eBay/Amazon/Etsy are not widely used and that her budget for this is very low, I will be hosting the web catalog on an existing server of mine, and that initially it wouldn't require to provide any ecommerce capability other than showing the catalog.