man, your dad is a mechanic, dont forget this, you can take him with you, and he can throughly check over the whole car even organise a day for him to take the car to his workshop and check it out. id go private, just get your car checked very good, and maek sure all parts are in good working order. i know why u want a GTS for and that is understandable for your age, a very sensible option i think. but use the number one thing that u have on your side, a family member that has mechanical knowledge. that is your best way to go, all car will have sum sort of problem some time in there life, its just a matter of time, but if you do this it will minimize the risk of anything bad happening to your car in the future from parts failure. so get crack in and find your ass a new ride!