I donated a bunch of stuff to the TG St Jude auction last year, forgot to specify shipping to the CONUS only. For the two items I had to ship to Canada, the shipping cost as much or more than the item auctioned for, one book, $35 shipping.
I donated my late wife's Barbie doll collection this year and remembered to specify CONUS only.
I give away a lot of tillering gizmos, not just to anyone but carefully selected folk who I know will use them. For years it cost me $1.85 to ship one anywhere in the US First Class, yesterday it was $2.35, shipping costs have gone way up.