Can I use a different bank ? Or does it have to be with one of theirs ?

Yes you can use your own finance; HOWEVER, not every bank is willing to work with them. For example Chase bank would not, because of the way drivers select wants to do it. Drivers select make profit out of financing, and they will pressure you in all possible way to use their finance sources while creating all kind of issues for outside finance. TOU CANNOT PAY OFF THEIR LOAN EARLY WITHOUT PENALTIES

You can get their financing and find a better rate after you drive away and pay their loan off with your new loan at whatever bank you want.

You can use your own. I suggest using a credit union. Better interest rate

You either pay cash or use their banks.

You MUST use theirs....How convenient