Non professional here for the first time looking for advice regarding finishing on a new build, we have had a contractor for the whole build and he elected to use a plasterer for the outside render. I did question this. We now have concerns and an RICS surveyor has agreed with us but the build is still refusing to take any responsibility on the render. He insist we chose a non-scratch finish were as in truth we didn't know exactly what that as so we asked for a consistent colour and texture. We now have 4 elevations that are completely different. One elevation was damaged with brick acid as he tried to clean the dark bricks above the render, his resolution was to acid wash the complete elevation, leaving the render a different light colour. There looks to be water ingress from the flashing around the oriel windows causing permanent stains. (the flat roof falls towards the wall instead of away). We are reticent to pay his final bill until the issues have been corrected. The edging and beading is either poor or non- existent. Other issues are decorative bricks not cleaned, engineering bricks not cleaning - any advice would be much appreciated as it looks like ot may end up in court