Once I went to buy styrofoam plates from a small shop run by an old & young man (likely father & son). I asked for the price then I said "Vendido !" like for saying "Sold !".
The two guys looked at me with such a face, they were not smiling at all and looked at each other, then looked at me again.
So I repeated, quite seriously "Vendido !". The shop was then very silent and I could guess something was going wrong.
After 90 seconds that semt an eternity, I repeated "Vendido" but explaining that I'm satisfied with the price, hence I would buy the product, which is why I said it's sold.
Then I realized that from the start, they thought I was saying "Bandido !"
lol...
Another one :
First month living in Argentina, not speaking a word of spanish. I go to a supermarket to buy eggs but couldn't find them. So I asked a clerk for "oeufs ?", then "eggs ?"... Well I tried and tried but the guy couldn't understand then I imitated the chicken even using sounds (cot cot codet !) and mimicking an egg coming out of my -oh well, you get it-.
I got my eggs !