Hi Ivan,
Yes, the Cart supports utilizing a mix of fixed and user enter pricing for products.
Smith Cart allows you to add the BuyNow module to multiple pages in your DNN portal. This allows you to create of an unlimited number of stores on your Web site to offer different product selections, presentations, payment methods, shipping rates, and tax setup. This is useful for such purposes as building a members-only store or creating a discount store for clearance items. The share flag can be useful in this context to share products across multiple buynow modules eliminating the need to reenter your products in each buynow module.
Thanks,