I often struggle with doubts about the correctness of the closings which I use. I'm not a native speaker and I'm worried that I'll make a mistake in the last part of the letter/e-mail.
I look forward to hearing from you soon. If you need any more information, please let me know
I hope to hear from you soon. If you need any more info, just drop me a line.
Could you let me know which closings are used the most?