Sorry, I can't really help you with whether or not you'd get financing. I'm not a banker, just someone who's bought or has been "on point" with family members buying new cars every year or so for the past 20 years.
A credit score of 750 is pretty good, but there's more to it than that. Your job status, age, employment history, banking history, residential history, & debt-to-income ratio all play a role. Every bank has different standards, and standards are a bit tighter than they were a few years ago.
I don't think NMAC has any special financing on the 370Z right now, so you're looking at "normal" financing. The dealership will likely try to steer you towards a bank that they have a relationship with. Banks give dealerships a cut of the financing fees, so they don't have your best interests (pardon the pun
) in mind when setting up your financing. Interest rates are historically low - a local credit union is advertising 1.9% for up to 60 months on 2010-2013 model-year cars. That's pretty crazy for a non-incentive rate.
The .9% that your folks got through Honda or Subaru was probably an incentive rate that was backed by the finance arms of the respective companies. You probably won't be able to get that low of a rate on the open market unless perhaps you're looking at a very short (12-24 month) term. Nissan has done 0% for up to 60 months on 370Z's in the past. I know last year they had it last spring on 2012's. You could want to wait a week and see if something special is announced in February.
In the absence of special manufacturer financing, I would at least look into arranging your own financing. Talk to your bank where you or your family have an existing relationship. They'll be happy to talk to you about a car loan. You can get real & honest answers about what it means to finance a car; amounts, required down payments, interest rates, terms, insurance requirements, and monthly payments. That removes the pressure of this from the dealership ritual, as you will walk in knowing exactly what that $xx,xxx OTD price means to you in terms of a monthly payment. It gives you a bit more negotiating power with the dealership, as it takes away an avenue for them to rip you off. It also potentially removes the embarrassment of being denied a loan at the dealership. One caveat though - don't go applying for car loans at a half-dozen banks all at once. That will ding your credit rating. If you've already filled out a credit application with the dealer (sounds like you did, since they told you your credit score), you might want to wait and see what they say.
I shouldn't assume anything, but if this is your first new car and if you're somewhat youngish, I would humbly suggest that you call your insurance agent before you buy the car. Insuring a Z sometimes isn't for the faint of heart. It will be
considerably more than your 2012 Forester.
Make sure you can afford the insurance premium
before you buy the car.
Good luck!