What If I Dont Pay The Balance On My Car After Its Repossessed?

The lender will likely file a law suit in court. The judge will rule in their favor since you signed a contract to purchase the vehicle.
The law suit will probably show on your credit report as unpaid and this may effect any future loans you might want.  Most lenders look at bankruptcy and repos to determine your credit worthiness.
I had a car repossessed and they hounded me for years. I was never able to pay the 3K+ balance on the loan due to unemployment and reduced income. They will write you regularly and phone to collect the debt.  A couple of years later they may well give you a chance to pay a smaller amount to clear the debt.

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