Hi Ajdre,
The NHSC scholarship is kind of unique, but there are other loan repayment/scholarship opportunities programs available through IHS and individual state governments for primary care commitments. There are also primary care loans that are fixed, relatively low-interest loans you can take out if you plan to go into a primary care specialty (some schools, like mine, only offer these loans to people after they match into a such a specialty since many people change their minds and the penalties are high if you don't follow through). Your financial aid office can help you determine what options are available to you, and you can do a web search also to see what your individual state offers.
The important thing to remember about all of these options is that they entail a significant service commitment and usually severe penalties if you fail to comply with the terms after accepting the money. For the NHSC scholarship for example, I believe you have to pay back 3X the money they give you if you don't meet your service obligation; and if you end up going into a primary care field other than family medicine, your job options to meet this obligation will be very limited.
If you are 100% sure you want to go into primary care and fulfill the terms of whatever program you go into (work in a rural area, on a reservation, etc), they may be worthwhile for you, but if you have ANY doubt, you should not commit yourself to something like this- especially not just for a car. You may think you want to go into a certain field now but feel very differently in a few years, either because of experiences in med school or changing life circumstances. Many people in my class started out interested in one thing and ended up going into something else- I think I could safely say this was true for the majority of us at some point in our 4 years. Loan repayment options exist if you do end up in primary care (and willing/able to uproot yourself and possibly a family after residency and move to a most likely rural area), and you don't have to make a decision or commitment now (when you haven't even started med school yet). I would just urge you to think long and carefully before signing any contracts, and if you do, make sure it is for the right reasons. Good luck.