Santiago isn't Sosua, nonetheless there are still some bad areas.
The iron bars are only a part of the defense you have in your house. I would also recommend and infrared system placed on the inside of each of the 4 walls. If you are not at the home for extended periods of times I'm pretty certain that you can get a security service that will be notified when the alarm goes off. I think it runs RD2-4k a month. You need to have a iron gate of the type to prevent cats and small dogs from entering.
As I first read your post I thought you were referring to the 4 "interior" walls of the house, but after reading the last sentence realized you meant the 'exterior" perimeter walls of the property.
There is "no way" you will prevent cats from climbing over the walls except perhaps (1) the wall is extremely high or perhaps (2) you install an electric fence unit on the top of the walls with multiple lines so that if a cat does make it to the top, the electric shock will tend to discourage them. Note also that cats will also squeeze under the space below the gate or even the space between the wall and the gate on those sliding gates. (the wheels on the gate keeps it elevated off the ground and gives space for critters (Rats, Cats, etc.) to enter.
Another problem with outdoor Infrared sensors of ANY type is that birds and/or lizards will also trigger an event, producing a false alarm.
Yet another problem with Infrared sensors is that those who knows what they are doing can simply walk right pass them and not trigger an alarm.
How many on here have outdoor motion sensor security lights and at times walk by them and the lights do not activate?
In the past I have had three (3) Infrared sensors across the front yard, yet my mother-in-law many times did not trigger any of them (And she walks slow). I have since solved that problem, now I always know when someone is out there. In the movies where the guys are robbing a bank, etc., note that they have to out-wit Infrared "BEAMS", not Infrared motion sensors. Chances of a thief coming to your yard and crawling on his belly is probably not going to happen. Unlike in the movies, Infrared beams are invisible.
Glass break detectors and mag switches on each window is a great way to go.
Mag switches can be placed if you wish for fully closed windows and also a set to allow the window to be open say 4 inches (If you do not have air condition). Breaking the glass or moving the window (Slide windows) will set off the alarm.
Jalousie windows are bad, bad, bad......
Video cameras showing all four (4) sides of the property in a quad image on a monitor(s) is very, very good to have, especially in those times when an outdoor sensor goes off. Another nice thing is to have an alarm system that "announces" which sensor has triggered, good to know so you know which way to point the shotgun.
Good security is not a "Plug and Play" module.
Don