Solo female travel · Mexico

Hi, I’m planning to leave around 25/01 for Mexico: Oaxaca first, then Chiapas, and then heading to Guatemala, starting with Panajachel. I’ve read a lot about how borders and transport can be dangerous. So, I’ve decided to travel with assistance and take a shuttle/minivan door-to-door from San Cristóbal de las Casas to Panajachel. There are lots of companies, and many have a bad reputation. Has anyone here had any experience with this? I’d love to hear any tips or advice. Thanks! Ed