If you want to go to Raja Ampat, you can book to Diving Company in Bali. It's not difficult to go to Bali, Indonesia from every country.
You didn't need hotels in Raja Ampat, you just liveaboard in cruise. Best time for diving in Raja Ampat and other Indonesia archipelago between March until October.
For further informations, you can find at
Bali Diving | Dive in Bali with Sea Safari Cruises
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