Since I didn't pre-book, I'm not sure how that works, but the busses that ran from Punta Arenas > Puerto Natales were run by a different company then Puerto Natales to the park. Given that you're staying in Punta Arenas and not Puerto Natales, it might be worthwhile to look into pre-booking. I suppose it's possible that busses run from Punta Arenas direct to the park, but I'm not aware of any and we didn't have that option.

For food, this was our menu that we packed for:

• Dinner 1 - rice, brocoli, sesame seeds, soy sauce
• Dinner 2 - rice, black beans, tortillas, tomato, aji, hot sauce
• Dinner 3 - pasta, tomato, olive oil, oregano, garlic
• Dinner 4 - quinoa, curry, zucchini, mushroom, coconut oil
• Dinner 5 - pasta, olive oil, oregano, garlic
• Dinner 6 - quinoa, blackbeans, lemon, aji

Breakfast was coffee and oats and snacks were the standard things; cliff bars, trail mix, etc ...

When you look at the map, the refugios have bathroom/shower facilities and camp stores with food & beer. You pay for this of course (and the food and beer is relatively expensive). Some of the campamentos have composting toilets, and they are free.

As for the weather, it varied quite a bit. Everything from clear skies and sunny 70's F to cloudy skies, rain, and 50 mph winds. As for night-time temps, the lowest we experienced was low 30's F. Overall though, the weather was pretty much perfect trekking weather. But it's just luck, and you really do have to prepare for everything.

And yes, it was every bit as amazing as I thought it would be. Would hike again. Depending on the direction you're traveling, and if you have the time, I would highly recommend adding paso John Gardner to the trek. Fantastic views of Grey Glacier, and if was one of my favorite hikes (although hands down the most difficult, and it was a day hike for us, so no packs)