I have heard that "Could you please...?" could lead some people to interpret it as being sarcastic.
The below is part of an email to colleagues I do not know and their boss to arrange a conference.
Request: Could you send me your presentation material by 9th September, please?
In this case, how should I write?
- Could you......, please?
- Could you please......?
- Could you kindly......?
- Could you......?
"I would appreciate it if ~" is used in other sentences in this email, so I would like to avoid it this time.