Public Phone Resources in Houston

Hey r/Houston, I work at a homeless clinic here in the city and we are trying to increase access to technology resources for our patient population. I know of a couple of programs available through the government's Lifeline program to get free cell phones, but a lot of these sadly require either a phone already or a physical mailing address, which many of our patients do not have access to. With this said, does anybody know of any places or resources in the city to either get phones for low-income people in person or places where people can use public phones for free/cheaply? I know the public library has public computers for use but only allows phone use in special circumstances. Thank you for the help!