Alessandro makes a fair point on the app, especially, it’s much easier to be sure you’re ordering the correct thing if you have the makers part number first, when ordering electronics like sensors, COP etc that are used in multiple vehicle platforms.
Straight forward stuff like brake line components, as long as you know a specific car model and year to use as a guide aren’t so bad. (I have a specific model/year Golf MK 4 spec’d on my account for instance, so I can order rear brake parts.)
Whereas with the Denso COPs for the S2000 I got the correct part number needed from the S2Ki forum first, as the original Denso units Honda fitted were phased out a few years ago and replaced by a newer part number.
The correct Denso items from Autodoc, in Denso brand packaging, were less than a third of the price Honda quoted to supply, at a discount, the same COP but in red Honda brand boxes.
Theyre my go to now, for service parts, as long as I don’t need them next day.