The Overland's small cost is nothing in the scheme of things. Much cheaper than buying new rolling stock, hiring staff, new signage that would come with a V/Line takeover.
Take care of the millions and the billions will take care of themselves.
As for the costs of a VLine service...
Rolling stock: Why buy new? There are Xplorer cars that will be retired from NSW service soon that could be acquired by offering $1 more than scrap price, use them on an interim basis until the eventual Geelong electrification releases VLocity sets to be fitted with standard gauge bogies.
Staff: this is something that Victoria already pays for as part of the package with Journey Beyond, but they should be able to cut down the number on board if they handle it in house. One driver, one customer facing attendant and a vending machine for catering should be fine.
Signage: If we assume a 6 car Xplorer fleet (4 in traffic plus 2 spares) then we need 12 VLine signs (one each side) which comes to $2023.08
, hardly the end of the world.