Ability to add a one time setup cost for a Pro Site subscriber

I was curious if there is any interest or plans to add the ability to add a one time setup cost for Pro Sites subscribers. As our levels increase we want to be able to add a one time cost to cover configuration of certain plugins like ecommerce or membership. As it stands now the subscriber has to create the site, login, upgrade and then would have to pay an outside transaction cost to cover the one time upgrades. It would be awesome if it was seamless.