We recommend Shopify in conjunction with Stock-Sync available in the Shopify App store for $5 a month. If you are setting up a new site try a free 14 day Shopify trial.
Step 1. Products.
Step 2. Collections and Navigation
Step 3. Inventory Maintenance
That's it. Your products are now onsite and in sync with our inventory. Watch out for new products. These will appear at the end of the product csv file. They can either be added individually or through an import.