What is the point of prospective buyers asking me to trade my Unusual to a friend first?

Recently, I unboxed a new Unusual Hat, and a couple of people have tried doing this to me:

Never tell your password to anyone.

ME.: hello

THEM: hey

THEM: how much for your unusuals in buds or keys?

ME: for the Janesary (with new effect) I was looking for around 2.5 buds

THEM: okay can you wait 5minutes ? il lget the buds first

ME: k

THEM: can i ask a rpoof before i get the buds?

ME: ?

THEM: do you have a trusted friend?

ME: you are the second person to ask this. I dont feel like doing this so I dont add more IDs to the list

THEM: can we use your trustred friend to hold your items until i get the buds?

ME: why does it matter

THEM: coz ive done this before i buy the items then they cancel our agreement.

ME: i dont have anyone else who wants to buy it

THEM: you can trade to your friend now and tell him dont give to me unless i get the buds

ME: i dont plan on doing that. I don't want to add more ids to the main list

THEM: so whats the name of your friend?

ME: his username is IDon'tPlanOnDoingThat

THEM: k

UPDATE

THEM:?

ME: ?

THEM: so you got a friend now?

(I will update that if he adds more).

What does this try to accomplish? I don't understand at all, but I don't plan on doing it.