BAD SERVICE and BAD REPAIRS

I booked my son's Sony Xperia Z3 in at Ceres branch for repairs (the frame was bent). I asked them to write down to make sure that the cell is waterproof. jobnr ***4. Someone phoned and e-mailed me a quotation of R2700 and I accepted. 9 days later I picked up the phone at Ceres branch but we immediately gave it back because something was loose inside the phone. I then asked them again to make sure that it is waterproof. Jobnr ***7. On 1 November I picked up the phone at the Ceres branch and paid the R2700. 2 days later I phoned the branch in Ceres, the owner of Ceres branch (Charl who was VERY rude) and the Vodashop in Tygervalley (Bazil de Klerk - who promised to fix it himself) and Vodacom Client service BUT nothing!. The phone was NOT waterproofed - My son tried to take pictures but immediately water went into the screen at the top left side of the phone. I took the phone in on Thursday again . Jobnr ***7. Today someone phoned me and gave me a quote of a R1000. How can I pay for that as well? Must I pay for their bad job? Thats pathetic! The woman phoned me a few minutes ago and told me it must be my son\s fault. This is BAD Service and BAD repair!"