Model-level reading
What changes the warranty calculation
The Audi A4 file contains 11 model years and 409 submitted complaints. The middle year in this set has 13 reports, giving each annual count a model-specific reference point.
2020 has the largest complaint count in the current file at 154. That does not establish a defect rate because sales volume and vehicle age differ across years.
Engine replacement or major internal repair carries the highest midpoint parts estimate among the applicable repair categories at $7,000. I would check whether that system remains under factory coverage before pricing an extra contract.