The actual energy to reach Earth orbit, at retail electric rates, is about what Walmart sells bags of potatoes for. It costs way more than that because we basically are using weapons of war (rockets descended from ballistic missiles) to do the job. The cost of a ballistic ICBM is limited by the value of the targets it destroys, so cost was not seriously limited.
As soon as billionaires rather than governments got involved, where cost came out of their own pocket, sanity began to reign. Carrier airplanes to raise launch efficiency, using the expensive aerospace hardware more than once, etc. Launch costs have room to drop about 50-fold from today's prices, and still be well above raw energy costs, the way airplane trips are well above fuel cost.
From Earth orbit to Mars we can build a chain of "truck stops" that supply food, fuel, and other necessities, rather than launching it all from here. Physics says it makes much more sense to get your supplies from a nearby asteroid than the bottom of a deep gravity well (Earth). The particular locations would be Earth-Moon L1, Mars Cycling Transfer Orbit, and Phobos. We already know of 12,000 Near-Earth asteroids, and the region between and near Mars should have just as many. They are farther away, so our Earth-based telescopes can't spot them as easily.
Using local materials, we can gain another 50-fold price reduction for the trip. So instead of $1 billion/seat, we are looking at $400K per person, which a corporation may well finance to get people to the work location.