Either one was fairly easy to get to the trail head. But the trail is not easy - probably moderate with a lot of elevation change. The closer one is probably shorter but when we were there you simply had to find a parking spot - lots of cars. If you are driving from Kahului the road is wicked. Lots of spots only one lane and two way traffic. We ended up backing up several times to allow traffic through. And a number of drivers do not understand how to handle a road like that.

No, you can't. Buses stop in Napili. It's still a bit of a drive from there. Walking is definitely not a good idea either. The road becomes narrow and windy and people drive way too fast on it. Too far to walk to anyway. I don't recommend using scooter's either...like I said, narrow windy road and people drive it too fast. I recommend renting a car to see the island, but book it on-line, you'll get a much bette rate then walking in and renting. Even if you're already there, book it on-line on your smart phone while your standing outside the car rental, then go in and pick it up, you'll safe a bundle. You can get vehicles for as little as $25-$30/day. Definitely worth it to get around the island. You really can't get lost. The bus system is good, but it will take you a long time to get around.