How set up a smart buzzer system for hard wired intercom systems?

Hello all,

I’m a soon-to-be host and very excited to create my listing. Like a lot of people, I’m trying to make it very easy for guests to check in and also make it easier for the hosts if I’m unable to be there.
I live in a gated townhouse community and guests would have to buzz in the intercom. I looked up Ringo or BuzzMeHome and they seem fine to me except for one problem: they cant work with intercom systems that are hard wired. My intercom system doesn’t have a phone number; instead all buzzes goes directly to my unit through my landline.

Is there another way for guests to buzz themselves in with a hard wired intercom system? Maybe there’s a way to have my landline phone automatically answer and buzz the “6” in? If there’s any hosts here that has experience in this, please do share! Would greatly appreciate it!