incredible23

i just bought a new system 2 aircon to replace the old one, but pipe are concealed so use back the old pipe. gas all leaked out after 1 week, the aircon service came and checked the aircon got no problem, so now they confirm it's the pipe leak, we have to change the pipe! may i know roughly what is the market price for change a new pipe? i dont mind to put the pipe outside the wall, as long as the aircon works and no leak again. thanks.