Comma and Line spaces when writing business email

Hello!

I got questions regarding two very simple but confusing things about writing emails.

1) Comma or no comma after Salutaion?

2) Should I leave Line Space/Spaces or not between the Complimentary Close and name when writing emails (not writing letters. Not leaving line spaces for signing signature on paper)? Because I've seen both examples in email writing teaching blogs.

-I am looking forward to hearing back from you soon.

Best regards,

Holly Jones

or

-I am looking forward to hearing back from you soon.

Best regards,

<LINE SPACE>

Holly Jones

Thanks in advance!

Ann