@PC - Multivendor Order and Shipping Ability

@PC - this is in regards to our live support discussion. I am setting up marketpress on multisite and looking to do the following: I have been around wordpress awhile but am new to multisite. I am working on setting up a site where local crafters can come and create a store of their own under my domain name. I want it to be subdomain driven. I want my site to be able to randomly display items from all stores. however checkout and shipping needs to be handled by each store owner but for me to somehow get a percentage of each sale. Am i right in thinking this can be done with marketpress? how would i create the random display is it possible with marketpress to set it up so the customer only has one check out experience or do they need to check out through multiple vendors if they are buying from more than one? does that break it out then and distribute information to each vendor then or would i have to do that? and by doing that how is shipping handled – from each vendor location or just from my location?