I think I've mentioned it in one of my posts, I'm in Croatia.
There's three limits on imported goods when it comes to our Customs office.
One, every parcel with value over 50eur gets opened and both VAT and customs duties are paid. There are some items that are exempt from customs duties but VAT gets paid.
To paraphrase the new song from the bearded ZZ folks, the government gotsta get paid.
Two, every parcel over half a kilo gets opened. All of the above applies.
Three, every package containing more than 20 or so of any one thing gets questioned. If you need more than 20 of a certain item, it cannot be considered "for personal use" and therefore must be imported through a freight company and ordered by a company registered for business that needs said item. I shudder to think what would happen if I ordered a 2500pc resistor kit off ebay for $10ish.
Naturally, once in a while a package slips through the cracks, intentionally or otherwise. It's just nothing one can count on.