How to get to Mendoza from Santiago
 

This site has given me invaluable info for upcoming trip. It seems easier to start our trip in Santiago and go to Mendoza, then return to Santiago to fly to Puerto Montt, lake crossing to Bariloche, then fly to Buenos Aires, rather than starting in Buenos Aires and flying to Mendoza, then back to BA to go to Bariloche.
Question is: given the high cost of car rental in Chile to go to Argentina, am I wrong to start in Santiago?

Lake crossing from Puerto Montt to Bariloche ? Only by car bus .

In January 2005 I did a detailed post on driving a rental car from Santiago to Mendoza and back. Click on my underlined screen name above and scroll down through my posts to find the right one.

Santiago and Mendoza look close on the map, but the drive took over 6 hours each way and we are experienced Latin American drivers. The drive over the Andes is beautiful and not overly scary, even the series of 30 switchbacks as you get near the Chile-Argentina border.....but I wouldn't consider it if there was even a possibility of snow.

If you would see the drive as part of the fun of your vacation, there is nothing wrong with starting in Santiago. But if your goal is to save time you might be better off just heading to Argentina.

If you want to do this complete trip, you better start in Santiago, then take a bus - one way to Mendoza is a 6 to 7 hours trip, that will cost you around 12 to 15 USD. Maybe same price on the way back or lower, I suggest you purchase your bus ticket coming back to Santiago once you arrive to the terminal in Mendoza .
Why just purchase one way? Well Bus companies have different hours and if you ask around probably get a good deal not only in price but on the time, as some bus companies return to Santiago very early and some a little later in the afternoon. Do some walking around the terminal is worth it.

The rest of your trip looks good.

for Aleta:
yes, you are wrong if you start in Santiago.

If you want to visit Mendoza, Santiago Puerto Montt and Bariloche the cheapest and most practical way is to

- take a plane to Mendoza($arg 300), -- cross by bus to Santiago (6hs=$Arg 50),(tickets have to be bought in advance in Chile or in Argentina. There are 3 services only.
- take a plane to Puerto Montt (around u$s 200),
- cross the lakes and get to Bariloche from where you come back to Buenos Aires.($Arg 411)

Very simple and cheap.
Good luck
milla