Do you guys rent golf carts there? And if yes, how much to rent one for the week?
Yes they have golf carts on site. I don't know what they charge specifically. I do know that the other golf cart rental companies charge for the day, 24 hrs runs between 500-550 pesos per 24hrs. It is well worth it so you can see the entire island. There is 7 or 8 companies that have them so you shouldn't have any issue finding one to rent and maybe you can get a better deal because you'll be renting for a week. Enjoy and have fun... Lots of great cafes on the Isla.
Get an answer from Hotel Posada Del Mar staff and past guests.