There have been a lot of posts on a lot of websites about her diet. If you do the research you will not give her your money.
Many people have had results, but the basic diet is not healthy and you are not only encouraged to starve yourself, but encouraged (and can even buy t-shirts that say this!) to achieve SNATT--semi nauseous all the time...
Follow Atkins or South Beach or a combination of the two, or just watch your carbs. She will take your money and you will join a community that will feed your eating disorder if you have one. The community here are 3FC is all you need, it is very supportive of health as well as weight loss.
Just speaking from experience here, you may hear some other responses but please avoid that diet and take care of yourself!!!