Check that there is proper tuition going on. Not just make them sit a paper while they make a cup of tea......
My DD's Tutor is pretty efficient In that regard, we had an initial assesment so we knew where she was in terms of capability and her weak areas. Once assessed we had a discussion with the tutor and they advised which areas in particular they will be focussing on and a plan of action for preparing her for the exam.
Our DD brings home her work so we can see her progress and have regular updates/meetings with the tutor to assess her progress.
I'm not sure how other tutors are working but I am very happy with ours. Most importantly the tutor has made our DD very confident and encourages her to ask all the right questions.