Personally, I think it is a great idea!
A most creative solution and you gain a car trailer in the process too.
Definitely a win-win solution!
The only negative I can think of, which hopefully won't be a problem (with proper precautions), is that trailers get stolen or broken into all the time. You would have to find a way to make absolutely sure that someone does not come up to hitch up in the night, lest the trailer and all your conveniently packaged special belongings disappear in a matter of seconds. That would be an absolute nightmare!
Depending on the safety/security of the surrounding areas, you might want to look into some way of disabling the trailer so that it cannot be easily stolen or broken into. Maybe remove a wheel or something? Motion-activated security lights too, if possible.
I will never forget something I saw years ago when I lived in a high rise on Broadway in Pacific Heights. A person was moving the next day, so they loaded their SUV with all their belongings the night before so that they could leave bright and early the next day. The garage was gated and thought to be pretty secure in one of SF's best neighborhoods. When they came downstairs the next day, everything was gone!
Ever since then, I have been extra careful since I have so much art, statues, and sentimental belongings.