Many of the bases on our furniture are in chrome. It is one of the most durable finishes and it will last for many years. These require no special maintenance except to wipe away stains and dirt to keep their shiny surface.
Oiled wood needs to be oiled 1-2 times a year, depending on where the sofa stands and what wear it is exposed to. If it is close to an element or in direct sunlight, it becomes dry faster and needs oil more often. When the base starts to look dry it's time to oil it.
We have lacquered bases in both wood and metal. These require no special maintenance except to wipe away stains and dirt.