Car modification costs can vary depending on the car's original price and availability of parts. For lower-end cars, modifications typically start around $500. These modifications can include changes to enhance performance or appearance. If you're looking at high-end cars, the cost of modifications tends to range from $1,000 to $1,500. High-end vehicles often require more intricate modifications, contributing to the higher price tag. Now, if your car is not in production anymore and finding parts is like a treasure hunt, get ready to spend $2,500 or more. This is because rare parts become harder to find and can be quite pricey.