I can no longer afford my car. If I surrender it, how negatively does that affect my credit score?

The answer depends on a number of factors. First, is the car a lease or a purchase? Second, have you spoken with your creditor (car dealership, financing company, bank, etc.) about refinancing or modifying your loan? Oftentimes a creditor will not be happy with a debtor that turns in its collateral to avoid an obligation. The creditor doesn't want the car, it wants its expectations of monthly payments and interest.

Try to contact the creditor with this in mind. Try to lower your monthly payments with the concept of providing the creditor what it wants -- monthly payments and interest. Just turning your car in will almost certainly lead to negative consequences on your credit report and credit score.

NOTE: This answer is not intended to be legal advice and should not be construed in that way. This answer does not create an attorney-client relationship and no such relationship may be created absent a signed retainer agreement. The author is licensed in Illinois only, and his answer is for educational purposes alone.