The Cocal website does not include availability for Cocal, only Vista Mar. I know, it doesn’t make sense. You have to call or email the Hotel. There are numbers listed on their website or
cocalcr@racsa.co.cr Last time I made my reservation entirely by email.
I would expect they would have rooms available for Green Season (the CR euphemism for rainy season) in mid Sept. I don’t notice much difference in the number of chicas at Cocal in rainy season, they still have bills to pay.
I did stay in a poolside room in May. The poolside bar is now open on weekends, with DJ and loud music until 2 am. If you have plans to sleep before then I would not recommend poolside. I booked a courtyard (parking lot) room for my stay in two weeks Sept 8-10.
Just to clarify, the only place to find chicas in Jaco is Cocal. You have the choice of then taking your find back to Crocs or other chica friendly hotels. I haven’t stayed at Crocs, but the consensus seems to be it is nicer than Cocal. I like the convenience of just walking to my room, instead of a taxi to another hotel. But, personal choice.