My parents travelled Mexico for several years, first in their MH and then in a 5th wheel. Their first trip down they went with a few other people, and they went through Juarez or Brownsville. They used to stay on a ranch in Etzatlan (which is near Guadalajara). The ranch had full hookups and several other Americans/Canadians staying there. One time they took my daughter (who was 6 at the time) with them. Actually they eventually built a house down there (sold it later when my dad got cancer).
I'm sure there are ways to find people to hook up with and travel to an area together. This is something I would like to do myself, but not being savvy would want to travel with someone who has done it before. I'm sure there are others here who have more info.