Customizing VPASP shopping card engine

Iam having a site [login to view URL] it runs with VPASP shopping card engine I want to add a make an offer Feature, for live demo look at below site [login to view URL] I want to have the same exact feature incorporated on to my cart and time runiing also must be exact the same ~~~Interested developer please write to me with live url example if you had made any previous project. try looking around this below url [login to view URL] you can see what Iam exactly talking about thanks