Hi Paul,
A wise choice, as it is very important to learn what chemical to use on what surface. If you use the wrong detergent on certain bricks or cement work, you will be looking at a big claim for damages against you.
I am not sure, but I think BICS might run a course on that, if not, do a search on the web. I have read a few UK suppliers who specialise in the equipment and chemicals and who also run courses as part of the package.
Good luck in your venture and I hope you find the info you need.
Andrew