Brazilophobia palliation

I've decided I'm only really worried about theft/mugging while I'm lugging everything between the airports and the hotels. Once I can leave most stuff in the hotel while I'm out and about, it's a much smaller deal if I get mugged. It's still quite a big deal, of course. :-)

So in order to minimise the number of airport-hotel journeys, I'm going to fly back from Rio to Sao Paulo the day before my onward flight to Chile and stay in the Marriott near the airport. There's a free shuttle bus and it's only a mile, so that should be pretty safe and easy. It's a bit pricey, but I think it's worth it to avoid the stress of an extra pair of taxi journeys with all my belongings. (I could arguably set the saving in taxi fare off against the higher price for the room anyway.) It will also make things more comfortable in the morning, as the flight to Santiago is at 11am and I think I need to check in 2.5-3h in advance.

I am probably planning on spending 6 nights in Sao Paulo, then flying on to Rio and staying 6 nights there before I fly back to Sao Paulo for the last night in the Marriott. I have e-mailed two cheap but OK-ish looking hotels, one in each city, but haven't heard back from them yet. Maybe this is the fabled slow pace of life in Latin America. :-) I'll give them another day or so then I'll probably have to start trying to find alternate hotels.

I'm completely unsure how to behave in the taxis from the airports to the hotels and back. Some guide books/websites insist you must put all your belongings in the boot (presumably to prevent people smashing the windows to grab stuff when stopped in traffic), while others insist that if you do that then you risk the taxi driver driving off with all your valuables when you get out. Sigh. My gut feeling would be to keep the hand luggage in the back with me and let the bigger suitcase go in the boot, but I have no experience of areas where in-transit attacks are even a remote possibility.