Just put the gas can on top

It struck me, while driving around in Argentina, that many car had a gas can on top of the car. Since labour is cheap in Argentina, I figured, this might be a 'we fill your gas can service while you sit at home'. I wouldn't be surprised: you can order ice cream to be delivered, right in time for desert; or you can even your prescription medication to be delivered. This comes in handy when you are on your sick bed.

Two scoops of chocolate con dulce de leche and a pack of morphine, please. Yes, to be delivered. Can you also add napkins and a siringe? Thanks!

I learned however that a gas can or, in the poorer neighbourhoods, a plastic soda bottle, ment 'for sale'.

How about putting a sign with details of the car, and the price? It won't fall of when you drive around.

(Oh, and if you were curious about a Peugeot 504 taxi. That's the one. Thousands of them roam the streets of Buenos Aires. As if it were the 80s.)