it’s not always like that. I didn’t pay a single cent on my catback exhaust and the springs where as I paid 16 bucks for a used S14 ECU that didn’t cost me more than 40USD shipped… and my rear z32 brakes cost me 400USD shipped, and customs was 110CDN.
I guess it all depends what you get, and what shipping company you pick. I still don’t fully understand how customs determines how much you should pay.