UPVC Door handles

I was asked by a customer to have a look at a composite door because the door had to be locked all the time otherwise anyone could walk in.I removed the handles to check the mechanism to see if there lock had a centre case which would allow the door to be shut and the the outside handle would not open the door. The centre case had 2 spindle holes so all it needed was new handles, i took some measurements contacted the supplier.  Rang the customer gave them a price,they wanted the job done.i ordeered the handles and when they arrived i fitted them whilst i was there i advised they had a thumb turn cylinder fitted so the could lock the door and not run the risk of being locked out because they left the key on the inside