I did regular speech therapy as a kid (think around the age of 7 to 9) for some years. Can't remember how much it helped, only remember I hated going there as a kid. Then in my early 20s I had a handful of sessions. I think this slightly helped, but not a lot. Costs were around 40 euros per session, but it was covered by insurance. A year ago I joined the McGuire Programme, which helped tremendously. The membership fee might seem expensive at first, but it's so worthed in my opinion and good value over time. You will have a lifelong membership and can rely on a very good support network to help you on your jouney. I left the first 3-day course with fluent speech feeling I was cured. Obviously this effect was temporary and I relapsed in some way. However with continiously working on my speech and the help of the programme I am able to maintain a pretty good level. I would highly recommend it, but you have to be prepared to put in a lot of time and effort. I am currently in the process of finding the right balance of how much work (which is sustainable for long-term) I need to put in to maintain a good level.