*update 21/09: event will probably be cancelled : I've been to a close car rental and there's one more permission it's needed to cross the borders, it's highly expensive (more 159900 pesos) and in this agency they said the reservation needs to be 4 days before. And there's a impossible warranty too (1.400.000 pesos). The event is impossible that way. Sorry but I'd read that it was only 20 dollars paid in the border. I'll try other car rentals, but now I'm not thinking it's too much different. The one I've been is Chilean United Rent a car. If any other solution is found i might go to mendoza by bus or hitchhiking. And there i try to find the cheapest tour, but I'm sure it won't be possible to go to everywhere we would. Sorry everybody =/ *update 20/09: event changed to 22/09 Hi, on 21/09 I'll be on Santiago and I intend to rent a car to do a tour to Mendoza, enjoying the beautiful and nice attractions between. I'm 31 years old and I'm used to drive. If we can reach at least +3 attendees it becomes really cheap and fun. I had done this in Munich,Germany and it was awesome! (couchsurfing.com/events/day-tour-by-car-to-linderhof-neuschwanstein) There's a picture in my profile from that trip. 21/09 is suggestion, near dates maybe possible (after 21/09) . It's a free tour where everyone attending have rights to give opinions to stay more in a place or to visit somewhere else that is not in the itinerary. It's really different and cheaper than doing tours with agencies, and it's possible to explore more places with more time on them, as we decide what time we go and come back. A similar tour like that going out from Mendoza is 56 dollars (http://www.viator.com/tours/Mendoza/Andes-Day-Trip-from-Mendoza-Including-Aconcagua-Uspallata-and-Puente-del-Inca/d931-5693ANDES). The trip is much much more cheaper, we're just going to split costs. . Going with 4 persons, estimated cost would be US$ 44. The estimated costs are: US$ 55 - shared: car rental US$ 60 - shared: fuel US$ 10 - p.p. : hostel in Mendoza (see list of possible ones below. US$ 20 - shared : taxes to cross borders to Argentina . The hostels: Lagares http://www.hostelworld.com/hosteldetails.php/Lagares-Hostel/Mendoza/6958?dateFrom=2015-09-21&dateTo=2015-09-22&sc_sau=avdc&sc_pos=1 Mendoza Inn http://www.hostelworld.com/hosteldetails.php/Mendoza-Inn/Mendoza/5783?dateFrom=2015-09-21&dateTo=2015-09-22&sc_sau=avdc&sc_pos=3 . Here's the itinerary: - leave Santiago really early , as soon as it's possible to rent a car and take the road - Stop at the road of "Los Caracoles" https://www.google.com/search?q=Los+Caracoles+Andes&tbm=isch - Visit "Laguna del Inca" at Portillo https://www.google.com/search?q=Laguna+del+Inca&tbm=isch - Cross "Cristo Redentor" Tunnel https://www.google.com/search?q=Cristo+Redentor"+Tunnel&tbm=isch - Visit and walk in Aconcagua Park https://www.google.com/search?q=parque+provincial+aconcagua&tbm=isch - Visit Puente del Inca https://www.google.com/search?q=Puente+del+Inca&tbm=isch - Uspallata (to-do) - Mendoza (to-do) .