Not Sure if this is a good idea

[m4a1mustang]

Not to be rude but it sounds like you should do a bit of research about vehicle financing.

1) Without us knowing the full details of the vehicle (You say touring + sport w/ 30k, but what year?) there's no way we can estimate the current value of the car

2) Giving the current owner their down payment AND assuming her current payments is absolutely ridiculous. You should only consider buying out her loan if it is less than or equal to what the car is actually worth.

3) If you are even remotely willing to take over a $25k note and give her $7k, you're far better off just buying a new Z.

4) When you're dealing with a seller making ridiculous demands like, "buy out my loan AND give me the $7k I put down on the car" you need to just walk away. This seller is unreasonable and either has no concept about how anything works or is trying to take advantage of you.