Why not skip the strobes and get collapsible reflectors to be held by somebody? Much easier that way. Especially if you want to do in water stuff... (I'll be there mid-april too... I doubt i'll bring my gear with me though)
I have done many shoots outdoors at beaches (well lakes for that matter, no nearby ocean where we live) and yes I have been able to do without strobes. But that was with 1 or 2 assistants helping me hold 1 or 2 collapsible reflectors. The benefit of a strobe is that I can shoot with no assistant if needed. We are going with a big group of friends that at this point offer their help but we know how it goes, once its party time everyone will bail out..LOL... I rather bring the strobe and not use it than kick myself for not bring it it... Yeah on-camera speedlite will be my very last choice, I have shot like that for emergency situations and not very happy with the results, I need to photoshop the heck out of a photo when shooting like that... Any more tips about possible good locations beside Playa Norte? Any close-by deserted beaches?
Temptation has a photographer , who is very professional. We got our photo shoot there. Very excellent quality photos. He charged us 300$ for 80 pics. He is good at work , very nice guy. He has desk near front desk.