Pronoun usage, is this okay?

[Jeremy Benezra]

One of my rentals I self-manage has 4 working women in their late 20's on the lease.  Instead of looking up and writing out there 4 first names in every email, when they email me and when I email them do you think its appropriate for me to simply open with:

Hi Ladies, 

Email content...


I don't want there to be any potential for that greeting to appear sexist or overly friendly or anything like that.  Thanks.