in readiness for exchange and completion

07:20 Sep 13, 2013 

I will take this into account.

07:15 Sep 13, 2013 

are 2 steps in the house-buying process in the UK that do not, I believe, have an exact equivalent in the FR system.
Exchange means the moment when the signed contracts are exchanged; this step does not, I believe, exist in FR, or rather, is normally simultaneous with the 'completion', which is when the sale is finally completed; neither event necessarily requires the simultaneous presence of both parties. After 'completion', the keys are handed over and transfer of ownership has taken place.
You might need to explain your way around it, or use some kind of expression with 'cession de propriété' and 'entrée en jouissance', but do note these are by no means truly equivalent terms!

Obviously in this case the solicitor handling the conveyancing is waiting for certain information prior to giving out their bank details for the final payment of the balance of the purchase prices, which must of course be done before the sale can be completed.