Because jet skis are Not Allowed in the National Park waters the only rental I know of is at the Westin Resort - maybe there is something in Coral Bay that I haven't heard of - be especially careful driving them here in STJ because so many people snorkel out and around some isolated points of land and are hardly visible to a fast moving jet ski.

Thank you I appreciate your suggestions. I know in STT they have organized guided jet ski tours which I guess are more safe. Maybe someone knows if they have something similar in STJ

Only from the Westin and you have to follow a guide.

Pia

Jet skis are a bit of a sore and controversial subject here. Have you considered taking an idyllic day sail or maybe renting a dinghy and gently putt-putting your way into beautiful little coves and beaches?

I can tell:) that is why we are now more into renting a kayak. Does anyone know where is the best place to do it? Also any suggestions for great snorkeling spots, caves or remote beaches? I would love to plan half a day trip and visit places where u can't get driving or walking. We were in STJ last year and it was awesome, we loved it. Going back this Saturday and we know it's going to be great! Definitely do not want to go against so I guess no jet ski:) thank you all for good advices!
Magda

Check out Arawak. I've heard great things about them and see the groups go out often. (I'm more of a float in the sea kind of person). http://www.arawakexp.com/ Hope you have a great time, let us know how it goes!

On the North shore you can rent kayaks at Cinnamon Bay Camps and also Maho Camps (I believe). In Coral Bay you can rent at Crabbys. You can find caves at Behive (I have read but not visited). As far as beaches only reachable by boat, I don't know of any that cannot be hiked to, There are some along the south shore east of Little Lamshur that are reachable only by hike or boat such as Europa. Again have only read, never visited.
Pick up a guide book and there is a lot you will find that would otherwise go un-noticed. I like my copy of Off the Beaten Path by Gerald Singer. It and others are available here on http://www.VItraders.com.