Hi simbo, Forget using a steam cleaner for carpet cleaning, there was a thread on this forum quite recently discussing the pros and cons of steam cleaners so check that out for more info, but what you need is an extraction machine.
Regarding what to use when cleaning upholstry i use solutions numbers 2 and 4 with great results, in fact i just got home from cleaning a huge beige three piece and i ache
it took 4 hours!!
There are plenty of factors to take into account when cleaning upholstry, due to so many types of fabric, so as others have stressed, training is very important if you dont want to ruin someones 3 piece.
Paul