I did a big block drive today after the house had been rendered,couldn`t get it all out,nightmare,i told customer before hand it wouldn`t all come out so he was happy with 95% of it out,just used turbo nozzle as test area scrubbed with acid was no better.The blirt said i`d blocked his drains when i went back to get paid,took a bucket of of cement out of drain and asked him did he not think the bloke who rendered might be to blame as i cleaned away from the house and showed him the bag of mud i still had in van from his joints,he swallowed his pie and gave me a tenner tip,b*stard,dyno rod would of charged him £200,ha ha.His drive looks like it was laid in reclaimed brick but what an improvement,as long as you let them know up front what to expect you`ll get paid.