I agree that $10K is out of line. How many flight hours are estimated in that?

Assuming that you have your commercial/instrument, and are current, and can do decent commercial maneuvers at this time, and have your writtens done for the CFI, it should be a seven to ten day course.

Flight time should be 10-20 hours depending on your skill level, and ground school should be another 5-20 hours depending on your knowledge level and the kind of questions known to your flight instructor to be asked by a particular examiner.

As a suggestion, pick up your ground instructor ratings before you go for your CFI. This is purely a paperwork exercise involving only written tests. This will get you into the books, and should cut down on the needed ground time with the instructor. It will also provide some brownie points with the examiner.

Joe