N541AC is $575 per hour with a flight instructor.

Multi-Engine add-on Rating: $7500 based on 8.5 hours flight instruction, 10 hours ground instruction, Aircraft rental for check-ride, Examiner Fee.

ATP: $5000 based on 5 hours flight instruction, 2 hours ground instruction, Aircraft rental for check-ride, Examiner Fee.  This is for pilots that are current and proficient in multi-engine aircraft and IFR current.