Realisitc ink cost projections?

[ScotJ]

Sorry if this has been covered before, but i'm getting into the digital side of print, but down the road see my self getting a DI press, or something of that nature, and wanted to get a feel for how much of savings I'll see over my typical click charge?

I know the cost will vary greatly depend on coverage, but with my grand format digital machines (8ft wide) I have a pretty good number to work from based on experience, and I was wondering what the consensus here was for the cost of ink on a 13x18, or any other sheet size for that matter.

Thanks in advance!