Just bought 88 non turbo Supra

[happigirl]

Hi,
I just bought my Supra, (automatic) and I have only two real concerns. It seems to idle kind of high, and when I shift it into any gear, whether it be forward or reverse, it lurches a little hard. Does anyone think this has to do with the idle, or could it be something else?
Also, if I go above 50-52 MPH, the car starts shaking, and I have to back it back down.. at lower speeds it is fine. I am very happy with it otherwise, but these two things really concern me. How expensive would repairing something like this be? Thank you so much for reading!