Most of the scams that are being pulled by the locals in Philippines, Vietnam, or Thailand start with a phony friendship.
Wherever you meet people (store clerks, vendors, hotel employees) they might ask you where you are from, only to reply: “Oh, that’s so interesting, because my cousin moves there next week!” It’s a guaranteed scam.
The crooks will invite you for dinner to meet the “cousin” (or uncle, sister, brother, etc), just so “you can explain to him what to be aware of when he moves. We could really use your help”. As travelers have nothing but time in their vacation and want to make friends, most of them accept the invitation, especially if is a free supper.
What’s about to happen is, while having a good time, the scammers will lure them into participating into all kinds of deals (see the Vietnamese Blackjack scam, Carpet deals scam, and the Gems transport scam).
How to avoid: every time you hear “My cousin will move there. Please come and meet him”, just thank him and say you have plans.