The gynae I visited for my first pregnancy increase their price by a huge margin and we want to be prudent with the second pregnancy. Do you think I should visit the same gynae as they have my medical record (diabetes & Thalassamia) or I should change?

If you feel the fees is something that you can't afford, you can switch your gynae and hospital. You can ask your gynae if you able to request a copy report of your medical history and pass to your new gynae yourself. Alternatively, you can get the tests again at your new gynae's clinic/hospital.