When

Comma-separated. Matched as whole words, any case.
A rule for one post wins over an every-post rule with the same keyword.

Public reply under the comment

One is picked at random each time, so replies don't look copied. Leave empty for no public reply.

Then in their DMs

Meta allows one message in reply to a comment until the person writes back, so end the first message with a nudge like "Reply YES".
Opens a chat with your sales number
All screens