I'm Lucy, and I'd be happy to answer your questions today.
Replies will go to the email address you used to post the ad, unless you posted a phone number in the ad. You don't have to get a Craigslist email address.
The email on the Craiglist ad is for your privacy. That redirects to your personal email. You can test it by sending an email to that address, and you'll see that you get it automatically.
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