Are vehicle purchase only filed once or every year while making payments on the vehicle?

If this is for a personal vehicle, not used in a business, you do not report the purchase or loan payments on a tax return.  Any sales taxes paid would be entered on a tax return as an itemized deduction in the year of purchase.

Personal vehicles are not reported on your tax return for any reason.

If you purchase a vehicle for use in a business, you list it as a business asset.  You should not have to list it again, but all your assets should remain in your tax file until you sell them or stop using them for business.  This also applies to other equipment, tools, and most other property used in the business that has a cost over $2500 and an expected life of more than 1 year.