The trip with Alexander was a good experience. Even though it was initially said that we would meet the guide on the US side , he ended up changing the location last minute and we needed to cross the border on our own.
After Alexander explained to us why he wouldn’t meet us on the US side, it was perfectly understandable to us.
We walked with him in the downtown area and stopped to taste tequila, eat tacos and stopped for a beer, and some historical buildings.
In general it was a very memorable experience, Alexander was a knowledgeable guide. The only downside was that waiting line (1h30-2h) to cross the border from Mexico to the US.