not every 1 has the money 2do it
if it does happpen the gov should help 2wards it 
Your having a laugh I am guessing, if you cannot afford £600 you should not be in business sorry if that sounds harsh, but come on I do the same job as you and now what you can earn
Right, I have my £600.00, I am in a very hard water area & need to have A RO & DI setup.
I live in a flat, so I can`t purify the water at home. I have asked family, but they are not prepared to set up a system on their properties.
Please advise further. 
easy done
I want something that looks proffesional, & not something like a pram with a beer keg on top.
im not a cowboy and no exactly what you need i started off just like you mate in a flat and ive never lookede back
Did not mean to sound facetious mate, but when asking for advice & receiving a reply saying "easy done", well it don`t really help anyone. 
You can do this for £600 or less , you will have to buy secondhand, there is always items for sale on here in the buy and sell section, tanks are normally about £50 ish, you can always use barrels (free from a car wash) you need an ro, these come up on here upto £100 for a secondhand ro, I sold one for £50 in working order, you need a di vessal, ibc tank if you wanted to make water at home, again you can get these free or upto £50, you can start off with a harris pole from b&Q as you starting pole, all in is less than £30 (do a search on youtube for waterfed pole for less than £30) I made a vid on it and how to make it. you can get a second hand hose reel for upto £50 seen them on here and ebay, pump and controller, look for red hat diving on ebay for there pumps they are cheap (not sure how long they last as not used them)
there are a few other little bits needed but as I said it can be done
if you are serious and want to do this I will help you.
Hope that helps a little
Ian