This summer I studied Spanish in Morelia, a city of about one million 3 hours driving East of Guadalajara (half way between Guadalajara and Mexico City). I'm writing this to give an idea of costs.
Flying down to Guadaljara is cheap! The awesome thing about traveling around in Mexico is that the bus system is so great. After a couple of weeks, a friend came down and joined me, we explored Morelia together and then we went by bus to Patzcuaro, Guanajuato, San Miguel de Allende, Zacatecas, and Guadalajara. It made a nice vacation!! And the weather is nice in the summer (average 2000 meters elevation, light rains about every other afternoon, although Guad is hotter).
These are mostly all tourist spots, but most of the tourists are Mexican (SMDA and Guad get some gringo tourists). We stayed in all decent hotels, no shared bathrooms (hey, friend was female, that was her boundary!), and I would say we paid an average of $28/night (inclusive) for a double/two-beds (so $14 per person). All of our rooms were large. We always stayed in the city center of our destination and so never actually needed to take taxis within the cities (maybe we could have saved by doing this).
Bus travel is probably about $6 per hour on average, and taxis are dirt cheap. I would say food is probably 50% of US cost for same quality/atmosphere. I tend to eat just two meals out per day when traveling.
Some principles of travel that I would like to practice in retirement, when I am not in such a hurry:
1) Don't move around all the time. You are retired! You can usually negotiate a weekly (or monthly!) rate at a hotel. In Guanajuato we were staying for three nights, so I asked for $2 off per night and got it. Many people at that hotel were long-termers.
2) Travel by bus/train when possible and enjoy the scenery, imbibe the culture, and talk to the locals on the way. And travel during the day!! That way you can see the scenery, and what is going on, maximize safety, and get to your next destination earlier to get a room.
3) Get up early. It is always safer during the day, you can do more things during the day, so it is more efficient to get up with the sun and go to bed earlier.
I am open to more retirement travel tips!! Bring 'em on!
Kramer