Hi Sweet talk
Welcome to the fringes of the wonderful world of fabric cleaning.
Would it be right of me, from reading your first post above, to presume that you would be working at the middle to high end of the market? Although within the lower end there can be many problems for the inexperienced upholstery cleaners, the upper levels tend to provide even more problems. My advice would be to follow the advice above and spend some time with an established and experienced technician. Another alternative, as a way of finding out what your market is like, is to work with an "Associate" who could take on all of your work, give you a little profit but without the risk or capital outlay. Think like a businessman. How many suites do you expect to clean in a month? 2? 4? What would be your outlay on machine, insurance, accessories and training? What price point are you looking at? How long would it take to get a return on your outlay?
If you were thinking of going into carpet cleaning too, I couldn't see a problem in your venture, but to feed off your existing market, at the lower volume, high risk end of our industry, within what I perceive to be the highest cost marketplace, on a low volume turnover would be a poor business decision. My apologies for being pessimistic, but from the information to hand, this is how I read the situation.
Safe and happy cleaning:)
Ken