Places to secure drop trailer?

We have elderly parents near St Joseph, Mo. I'm not exactly an in-law, and it's crazy to drive those miles and not make money, then deliver and not drive unloaded, so that basically takes up the entire time I'm there while the truck is moving. However I can't get away with it all, and will have to stay overnight with the folks a few nights and not in a hotel, where I could drop the trailer. In general where on the internet can I find secure drop yards? Specifically around the St. Joseph, Mo area, but I'm going to get a working vacation with the wife out of this so I'm going to need other locations as well. Can you tell I've already tried to get out of this and explored other avenues? When I've dropped my trailer from breakdown, or at hotels, I have a 1 inch hitch lock, and lock every tire with 1 inch bike chains, as I use $450 Continental HTL2 17.5in tires on my car trailer. Only ones I've found that won't wear and blow significantly. So it'll take 3 people still probably 30 minutes to steal it so the drop yard doesn't have to be security guard secure. Thanks for the info. Chris