Increasing the safety of my Dodge Ram Van

Hi,

I'm told my Van is really easily opened by criminals without using a
key, simply by wedging a tool at the right place intp the door gap
below the lock and giving it a nice strong upwards blow.

Seeing that I will be travelling in it and occasionally sleeping
inside it, using it as a kind of makeshift RV - is there an easy way
to install double locking or better locks or just generally making it
a bit safer?

I even thought about having eyelets welded to the doors and using
padlocks... but I'd prefer more, ahm, elegant solutions.

Regards
Peter