Tradelines and credit repair are often mentioned together but they solve different problems.
Credit repair
Focuses on the existing report — identifying inaccurate or unverifiable items and disputing them under FCRA. It cannot remove accurate negative items.
Tradelines
Focus on adding new positive data points to the file, typically through authorized user accounts on seasoned cards.
When both apply
A profile with disputable inaccuracies AND a thin positive file may benefit from a coordinated strategy. But every profile is different, and neither service is right for everyone. Consultation first, strategy second.