Locking the front door for long trips is a good idea.
I've epoxy'd a piece of wood (paint stirring stick) in a couple of trailers as a speed bump for the latch to go over before it will unlock.
Give that a try?
Jim


On Tuesday, September 9, 2014 7:25:56 AM UTC-7, MQ wrote:
If it is a metal top from before 1990 no dice on keys from Cobra...they are right for later trailers though. From what you describe I do not think that keys would help anyway. Install a hasp as you mentioned and Mark suggests.