Palau on a budget??

I'm thinking of going to Palau, as cheaply as possible. Has anyone else tried? How much did you spend in a week? Is camping possible (at official sites or random places?).
Also, what about cycling? I would happily tour the island on my bike... is this common? possible?

The problem with Palau on a budget is that the best bits are on and under the water. To go to Palau without going out to the Rock Islands, and either diving or snorkeling- it would be so sad! Thus, a conundrum. And if you have spent all that money to get there- you need to save some to do these things. You can stay in cheap motels, bike around- but you HAVE to go out to see the wonders.