I think the numbers that folks here are quoting a probably on the low side, unless you're looking at training at a non "mainstream" program. If you're training at Flight Safety, Simuflite, or CAE, I would expect to pay anywhere from $10K all the way up to $35K (or more for a G550 type), not including expenses.

My initial type rating in the Citation 560 (Encore) at FSI Wichita was around $21K + hotel/food/transportation, IIRC.