Hi billyc
Is it all stonework?
Bricks are easy but stonework can be a bit of a pain.
Tensids chemicals are great... am in the middle of a job at the moment which is majority brick but with stone 'topstones'. The bricks (90% of the job) are coming up great but for heavily polluted stone areas, it needs a prewash and then restoration cleaner afterwards... doubles the cost of the chemicals and the time it takes to do the job. I normally quote between £12 and £18 per square metre so if it is all stone I would err towards the latter if I were you.
I would expect to complete between 40 and 50 square metres a day.
Nice little earner mate, good luck.
Andy