An ambitious potential client has asked us to build a scalable multi-vendor e-commerce platform, with all the luxuries of a modern e-commerce site (various payment methods, SEO, marketing campaigns, fraud detection, etc.)<p>The budget is tight - enough to cover two months of initial development.<p>Using off-the-shelf CMS/e-commerce frameworks, is this at all realistic?<p>We're considering developing a proof of concept in Umbraco/uCommerce or nopCommerce (both .NET solutions) to get a feel for things. But is it worth the undertaking?