I did someone a favour the other day without expecting anything in return. Then she insisted on returning the favour somehow, so I asked her to do a little something for me.
I wonder if the following sounds idiomatic enough to express the idea of mutual back scratching?
Dans ce cas-là, voyons ça comme un échange de bons procédés !
I cannot seem to find a dictionary entry or a webpage that refers to this expression as a direct translation of the "you scratch my back, I’ll scratch yours". So I'm not sure.
At any rate, I’m looking for an expression to denote a casual quid pro quo arrangement where you agree to scratch someone’s back so they scratch yours.