Everything but the kitchen sink
A 1 Gift Container of Holding Power used by Mikey Rayes, created by Serpentail.
From the outside Mikey's shipping container appears to be normal. It measures 8 feet wide, 40 feet long, and 8 and a half feet tall. The back has a securely locked double doors. The Left side of the crate also opens. It can be unlocked and swung upwards to access the crate from the side. Either of these doors are supernaturally locked and can only be opened by Mikey himself. To do so he traces a precise symbol onto the surface of the lock with one of his picks, causing it to spring open.
The inside of the crate opens into a pocket dimension, 5 times larger than it would otherwise be, totaling to 1600 square feet of floor space. The pocket dimension appears as a garage with a concrete floor and steel walls. It is illuminated by a series of tube lights inset to the ceiling. By tracing the same symbol he uses to get in, Mikey is able to open any given section of the wall to either of the doors.
You possess a Shipping crate that holds 5x times what it should, given its dimensions. There is no cost to use your container. Objects stored inside are weightless.
Living things can be stored in your Shipping crate. But they will have access to anything else that is inside and may attempt to break free, damaging or destroying the Shipping crate in the process.
If your Shipping crate is destroyed, things inside may get out, and it will cease to function, but it can be repaired.