When this happens, I let someone know that I could rewrite it and charge them full price for a speech, but that MY recommendation is to keep THEIR voice. I recommend having me just lend a hand with smoothing out the speech for a much lower rate.
This made me think of the topic of when someone really needs speech writing help. In a lot of professional settings, it's important for a lot of reasons. Business people often don't have time to get the speech written, there is research to be done, complex organization, etc. So unless they are very good writers and have the time, it's a good idea to outsource the work to a speech writer.
But in so many personal or social speeches, writing one's own speech almost can't fail. You know your voice, you know your stories, and everyone listening wants you to succeed. They're not expecting a lot. They're with you at an event to share in something. In most of these cases, a speech writer isn't needed. No point in reaching out for help.
Still, I can't deny that a lot of people are very nervous about giving a speech, even in such a friendly setting. They WANT to feel that a professional has helped to organize their words. Someone else might be very busy with work and has the extra funds for help. That's ok too. In other cases, someone wants to have a real impact, even though it's just a social setting. Well, this is another reason someone might get help.
Since these events still rely on the personal stories of the speaker, I always charge less for social speeches than I do for business speeches. It's much more a matter of getting personal information and then organizing it and making it flow for the best possible speech.
At the end of the day, choosing to get help for a speech is a personal decision and comes down to how you feel, what you're trying to do, and what you're confident in being able to do. (Plus budget.) I encourage you to believe that people in a social setting are rooting for you and that you don't need to spend on getting help. But if you DO want a hand, I really understand that and try to make my help as affordable as possible while still providing high quality service and revisions for a flat fee.