What is the best option to send luggage from Germany to Central America?

I am moving from Berlin to Guatemala and need to send personal belongings because I am flying with an airline that charges too much for extra luggage. I want to send about 50 kilos in total.

should I get a portable GPS unit or choose the factory installed option for my new car?

the top of the line portable one I’m looking at is a mere 600 bucks and it offers a ton more features and better looking maps than the factory option, making me reckon the auto maker should stick to making cars and not GPS units.
still, I like how its cleanly integrated into the car, [...]