As a singer without any formal vocal training, you would probably have wondered whether to hire a vocal coach to train your singing voice. Well, your procrastination is hurting your singing career.
Just name me any famous singer who never had any vocal training? Yes, some of them may have gotten popular without any formal singing lessons but all these popular singers, without exception realized that they have to engage a vocal coach at one time or another take their spectacular singing career to superstardom and to stay up there.
So what makes you think that you do not need vocal lessons? If you are already singing professionally, then it is vital that you take up voice training to separate you from the mediocre singers. This is how you can get noticed when you are above the pack and above your singing competitors.
If others do not believe in vocal training and you do, then you would already have won because you will be singing much better and control higher fees for your performances.
You need to take care and respect for your voice. That is your musical instrument and your voice determines whether you succeed or fail in your singing...