We flew in to Kahului and the guy we rented the truck from met us at the airport with our home on wheels for the weekend. We had an awesome experience with this truck/tent. It folds down in just a few easy steps and then you're back on the road again. It had a foam mattress inside, and the back of the car was stocked with everything you might need for camping. We would definitely recommend it!
We didn't know much about Maui before visiting, but we heard sunrise at Haleakala Crater was too beautiful to miss, so we headed up toward the summit our very first night. It was dark by the time we were driving up the mountain and it was a little scary! There are no lights and no guardrails on the road and it felt like you could fall off the side... and just keep falling! During the day, it's a lot less sketchy, but driving up a mountain through fog, feeling like you're entering some kind of Stranger Things dimension was definitely an adventure.
We found out you do need to have tickets to enter the summit, so get those ahead of time! There is also a $25 entrance fee for the park. We were lucky to have a park pass from the guy we rented the car from - but you can pay at the entrance if you don't have one. We camped the first night at Hosmer Grove, which is a tiny little campsite on the way up to the summit. There's not much at this site - pit toilets and a couple of picnic tables and it was really full when we arrived, so if you need a spot on the ground you'll have to get there earlier than we did, which was around 10 PM. But, we found a place to park a short distance from the actual campground, popped up our tent and settled in under the most gorgeous black sky full of stars.
We woke up around 4:30 the next morning up to drive the rest of the way to the summit. There's bound to be a line of cars, so check the sunrise time and make sure you leave early enough to make it up and settle in. It was also 30 degrees when we got up there, so bring your warm clothes. All that said, sunrise at Haleakala - 10,000 feet above sea level - lived up to the hype. It was a beautiful experience.