Car registration number selection charge is RM210 for JPJ Selangor. I guess the same charge applies to other states as well. What you need to do:
1. Fill up the JPJ form with the new car owner information and signature.
2. A copy of the new car owner Mykad (front and back)
3. Go to JPJ, take ur q number and wait. Make sure u have 3 to 4 reg number options in your mind or just write them on a piece of paper.
4. Your number is up, approach the counter, give the form and mykad copy and tell them the number that you want. If not available then tell them your second option and so on.
5. If number is available then you pay the RM210 charges and the counter rep will give you the confirmation slip or just printout on your form.
6. That is your registration number for your new car and you have to register it within 1 month. Else, JPJ forfeit your money and the number is back into the selection pool.
7. Give the confirmation slip or the form to your car SA to proceed with the registration.
All my cars and bike having nice three digit numbers.