веЗти
насчет

благодарю за исправления,но я ожидала помощь в переводе)

that belong to practically everybody - неудачно IMO. Так говорят о чем-то большом, что принадлежит всем.

thigs that almost everyone has in their possession - но это тоже не совсем "с собой"
has on them? has in their (cabin) luggage?

It's no secret that you shouldn't take seashells and pebbles/rocks from Turkey or Egypt. This is prohibited so as all beaches don't get stripped away by (souvenir-seeking) tourists. But you may be asked questions even about ordinary things/items nearly everyone has on them when going through the customs.

да, насчет belong Вы, наверное, правы...

Obviously everybody doesn't know - this is the first I hear of it. I would say: "Everyone should know better than to take shells and pebbles out of Turkey and Egypt. These parameters are in place to keep tourists from walking off with entire beaches as souvenirs. However disputes sometimes come up at border checkpoints over objects that almost everybody tends to have on them."

BAN implies that it was permitted (and even encouraged) at one time, and then was stopped.

TURN BEACHES INTO SOUVENIRS sounds bizarre to me.

PROBLEMS ARISE sounds like things people are carrying with them are causing problems - like cellphones interfering with electronic devices. I believe they're referring to disputes here - objects that are called into question and possibly confiscated by border authorities.

That was a really tough one! Thanks a lot. 🙏

Anytime)))