Carlos the Gardener

First Encounter
You first encounter Carlos in the mission Complications where you have to repo Jimmy De Santa's newly bought BeeJay XL for Simeon Yetarian. You have to knock him out before entering the house.

Conversations
As Michael you can have conversations with Carlos by saying "What's up?" and "Keep up the good work." but he doesn't respond. You can also catch him on his phone talking and he'll say "I'll get back to work in a minute."