did a job today which was a new carpet and they just wanted in protecting. I thought i would do it exactly to the book and give the costings here.
bought 5lts of Chemspec stain shield professional concentrate (CSPC) which I believe is the best protector on the market, cost £73 inc VAT.
the carpet was 24sq/m which according to the instructions required slightly less than 5 litres of RTU solution, CSPC is mixed at 4-1 making 5lts of RTU protector.
so for this job I used 1lt of concentrate which works out at £14.60p so the carpet cost 60p a square metre to protect using the a good quality protector.
it took 2 of us 35mins from turning up to driving away.