They want bricks right?
I feel your pain.
In one of my previous parking locations above I was struggling to get the bikes insured. They were parked IN FRONT of the guard that was at the post nearly 24/7. The parking door was closed/locked from 8pm to 6am, cameras, lasers, rabid dogs and all...
NO NO.
But... hey, a shed somewhere in a back alley with a plywood door a 96 years old can easily kick down:
yes no problem.
I kept paying the higher fees until I was able to get them insured that way because I felt it was safer to keep them in the residential car park than aforementioned shed.
PS.
I have the bikes chained and one of them is chained to the floor with a ground anchor and Pragmasys chain and pin going through the frame, but I generally never declare it on the policy. It doesn't affect price that much and you might be in a lot of pain if the bike is stolen without the declared security on.