How much does it cost to fuel a Starship?

Inquiring minds want to know: What's the price tag for powering a Starship? Is it a budget-busting endeavor or a relatively affordable feat? What factors come into play when calculating the cost of fueling such a colossal vessel? And, are there any innovative technologies on the horizon that could potentially reduce these costs? Let's delve into the mystery and uncover the answer to the question: "How much does it cost to fuel a Starship?