Myself, if a cue is bringing 1k to 3k, not a huge deal. Use PayPal and be done with it.
If its bringing 4k to 6k, face to face or third party only.
If its bringing 7k and up, wall, third party only.
I remember selling a cue for $16,500 face to face in cash. There was a problem after sale.
I gave him the option for refund minus 3% within 30 days if cue had original tip and was unchalked with all else being good.
Lol, I screwed up and made the receipt out for $19,500 instead of the actual $16,500 and marked it paid.
Well, a few days later I get a call. Fellow says he wants to return. I say ok, it will be 3% free. He said ok. He sent me copy of receipt and I come unglued.
There was nothing I could do. I got took since he paid cash, I had no proof he didn't pay the higher amount but, he had a signed receipt saying he did.
I refunded the money,
You can and will get screwed if sell enough cues at some point unless you learn to be safe and be extremely tedious in your transactions whether face to face, online, money order or check.
Again:
Small amounts = PayPal and done
Larger amounts = third party for protection
As for the white stuff, shouldn't matter unless its going through customs. Even then, sometimes they miss it and let it slip by.
Good luck.