That's going to be the very end of rainy season (officially it ends Nov. 15). You'll likely get some beautiful days but you might get some crazy downpours. I've been there in November 3 or 4 times and gotten very little rain and other times been reminded that it is rainy season. So bring some rain gear or at a very minimum get some disposable ponchos and have them with you when you're out and about.
The Montezuma Film Festival used to be in November but I think they do that in June now (but they had some sub-festivals so just ask about it while you're there); I'm not a big bar person (not much else to do at night) so to see some unique movies is very interesting to me.
I've never stayed there but anyone I ever talked to while I was in Montezuma who was there seemed to like it.
You definitely want to check out the waterfalls that are right there. 90 foot and 40 foot, you don't need a tour to go there but you can't really go when it's been raining a lot. It's beautiful. If I have nothing else on my agenda for the day I go every day I'm in Montezuma.
2 hours NE up the beach is another waterfall that kind of pours into the ocean.
Cabo Blaco is a nearby national park. Very nice, it's the countries most preserved park. (Closed Monday and Tuesday). Long hike 2+ hours to the beach or a shorter hike 90+ minutes round trip (those are the only paths that are open). Lots of animals if you're quiet and stand still every so often.
Don't ever leave your belongings unattended even for a minute. The locals will tell you that over and over. Mostly passive crime (especially in that area).
You said "I" and not "we":
I travel alone occasionally so I use some of the PacSafe (search "pacsafe Anti-Theft daysafe") backpack that is lockable when I go swimming and lock it to a tree; they'd need wire cutters or a machete to open it (they actually might have a machete but they can't open it subtly. I also use this to lock up things in my hotel room when I don't have a safe.