Transplants are expensive, but the amount billed to your insurance is not a meaningful number in any way. Hospitals don't actually expect insurers to pay that; they set the number absurdly high as a starting point for the back-and-forth negotiations. This is particularly true for very expensive procedures which are almost always paid for by private insurance - both because of the expense, but in some cases by law.

(On that note, even looking at the amount paid by your insurance is misleading as well, because if you're on private insurance, you're paying not just for your own care, but to cover the care of people who are on Medicare and Medicaid, since private insurers are required to cover the costs of those patients' care as well. This is especially true for high-end, expensive, and/or chronic or terminal treatments like dialysis.)

The only major variable you should try to optimize is wait list time. Outcomes are roughly comparable across centers and are monitored by the government.