Commuter trains aren't cheap. They can cost taxpayers anywhere from $1.3 million to $10 million a mile to build. Highways aren't cheap either. Consider what's in store for Interstate 26. Planners and engineers are working on plans to add two lanes to I-26 from the Neck Area through North Charleston, about 8.2 miles. If and when the state finishes this expansion, an eight-lane highway will run ...