Identify the installed product
The panel pattern alone is not a reliable parts reference. Ask how the manufacturer, construction, dimensions and connection details will be confirmed. A section from a similar-looking collection may not suit the original assembly, even if the exterior design appears close.
Discuss finish differences before ordering
Existing sections may have weathered or been repainted. A newly supplied section can therefore look different even when it is the appropriate product. Agree whether the expected result is acceptable and who would handle any manufacturer-approved finishing work.
Compare the alternatives clearly
If a compatible section is unavailable or wider damage exists, ask for the reason a full replacement is recommended. Keep repairability, appearance preference and optional upgrades separate in the estimate. That makes the choice more useful than simply being told that a new door would look better.
Your questions
Can a matching paint color prove that a replacement section is compatible?
No. Appearance and construction suitability are separate checks.
Does one dent always justify a complete door replacement?
No. The damage, product availability and condition of the assembly need assessment.
What should I compare in a panel repair and whole-door replacement quote?
Ask for the compatible section specification and any related damage in the repair option. For full replacement, compare the complete assembly, removal and installation scope. Keep a desire for a new appearance separate from work needed for the door to function correctly.