Can anyone suggest a good tour operator for this 3/4 day jeep trek.
The two of us are looking for any advice and experience on this subject including whether we can wait to book it in Uyuni or whether we should book it in advance. Any advice and experience of this trip would be greatly appreciated.
I had been in Uyuni two years ago. I didn't go to San Pedro Atacama but there were tour to go there. In my opinion you will find similar or simply the same price in different agencies and you will go in the same jeep independently in what agency you buy the ticket.
I did this trip twice. The first time 2 year ago, the last time last year. I did it in both directions, San-Pedro to Uyuni and reverse. You can book the day before you leave in San Pedro or Uyuni as there are many travel agencies organizing this tour. Some of them are more expensive, they offer better food, sleeping bags, but they all do the same trip.
I always went with the cheapest companies, and never experienced any problems. The last time I went with Playa Blanca. We even slept one night in the hotel completely made of salt (caleed Playa Blanca 2, just outside the salar).
You can also book from La Paz. If you book from here the trip from La Paz to Uyuni can be included in the price for the whole trip. Just check and compare the different agencies when you are there. Be sure they write all the things you are going to visit on paper, so that they don't skip anything!
It's really an amazing trip, maybe the most beautifull scenery I've seen in Sout America.