PrestaShop is a free, open-source ecommerce solution and can be hosted on-premise. However, while PrestaShop is free to download, once merchants factor in the costs of hosting, technical support, security patches, and version updates, the total cost of ownership can be higher than many merchants anticipate.
While PrestaShop can be a heavily customizable solution, it can also be difficult to manage and maintain long-term.
BigCommerce, on the other hand, is an Open SaaS platform and always includes ecommerce hosting, maintenance and automatic security patching as part of the monthly subscription fee. With the combined benefits of open source and SaaS, BigCommerce allows merchants to integrate to their existing systems and easily install third-party applications without complicating the management and upkeep of their online store.