The usual Dominican solution to doors is to have an ironmonger made a door of wrought iron that opens out. These can be decorative and attractive. The interior door will open towards the inside.
I have seen these steel bar doors with a lock installed, but the tradition is to put a padlock on it.
One can buy a large variety of kickass padlocks in the US, and they are portable, and fit in a suitcase, unlike maximum security doors.
On the inside door, you can install a deadbolt. It might not be burglary proof, but it would make it harder to get in than chiseling through the concrete.
Or take a look at the variety of clever door reinforcing systems available on the net. Its not just the door, its also the frame that needs to be reinforced. Some of the security systems use a bar that drops into a small hole drilled in the floor and have a metal bar that runs the width of the door including the frame. Not sure but it might be called a fox lock. Even with just an average wooden door no one is getting in. In my view much cheaper and secure than just a strong door. Advantage is that you keep your door and do not have a door that makes the home look like a prison. Good luck