Rarotonga for a week...

Hi there. I've only got a week on Rarotonga (early June) and would love to get some tips from people who've visited. I've been reading lots of past posts but the more info, the better. Any advice on the cross island hike, places to stay & eat, car hire for a day or two, snorkeling, must see sights, awesome beaches, great activities, etc will be very much appreciated. I've not got great deal of time to plan this trip. I'm a single back-packer on low-end to mid-range budget.
Thanks in advance for any & all words of wisdom!! :-)

We did the cross island hike without employing a guide. You probably don't need to hire a car the bus service is very good and cheap. Snorkeling was nothing wonderful possibly the best around The Fruits of Rarotonga beach.