Looks as if maydup is of the opinion that anyone can hang paper and paint. Which is true, they can. But, most would not be able to do a good enough job to charge for their services. Only takes one or two botched or unsatisfactory jobs for a reputation to be tarnished beyond recovery. I've lost count of the number of times i've been called in by the lady of the house to rectify the efforts of the man of the house.
You could, of course, RUN a painting and decorating business, employing proper staff, but to be a success in any business, your heart has to be in it.