Looked around for this topic and saw nothing so here goes. Many of us have purchased Mods and Add-Ons for our sites, be the vB, IPB or based on other software. Now we are looking to migrate to XenForo and would like to see some of the same items we have ported to XenForo. Assuming one has kept up with the license fees. If the creator of said Mods and Add-Ons were to port the same to XenForo what do you expect to pay if anything? As an example. If one was to move to say a Mac from a PC and you already owned the MS Office Suite, MS does not offer a discount on the different version.