Self Storage Concern

9 months is not enough time for normal weather extremes to cause any problems. Now if we were talking many many years the weather extremes could cause the plastic to become brittle. I believe the only thing you would have to worry about over 9 months would be if they got wet and even then the plastic would be OK but any paper/cardboard would be toast.

When storing things other than inside my house I've totally switched over to the plastic tubs/containers.

I agree on the suggestions about decals but to be honest if it were me I wouldn't bother. Not for a 9 month time period.

I'd agree with everyone that the plastic should be fine, keeping in mind if you find a kit down the road that has a "warped" part, a little heat from a hair dryer or something will fix that.  But the decals.....REMOVE and either file them or place them in zip-lock bags!  The humidity will ruin a sheet of decals in a heartbeat.  Other than that, don't over pack a box where they are crushing each other.  Hope this helps.

Eagle90

The plastic should be ok so long the contents aren't crushed under a large weight, which will cause warping. I'd get any decals out of there, and keep them in a ziploc bag in the house so they won't crack up. If you have any car kits, remove the vinyl tires, they'll react with any plastic that they're in contact with, and ruin the plastic.

Glenn

I'd worry less about the temperature and more about the humidity. Here in Colorado it's pretty dry, but I reckon in your neck of the woods, not so much. That being said, with that many models, I'm not sure how I'd go about protecting them from humid air.

I don't know the cost, but the PODS (Portable On Demand Storage) are advertised as being kept inside a warehouse. Might be worth checking.

I know the weather conditions here in the UK are not the same as were you are. But I had my models in a storage unit for about 5 years after my separation. And they are now stored in an outside shed. I have not had any problems even with the kits that I have had for years.

The only thing that could be affected is the decals. If you are concerned, you could remove them from the boxes' and store them in a folder which you might be able to leave somewhere else other than the storage unit.

How cold does it get in the winter.