Lola, i have the same problem, i can fit fine in to most size 14 jeans from the legs, but the stomach area is always tight or doesnt fastened up! A size 16 would most of the time be too big! I am just being patient and just doing my regular exercises now, but still i have a huge belly, honestly i really do
They charge for courses where I live near, but if you just wanted a one off then its approx £65-£70 a throw, not cheap but I'm a bit scared of them.