Ranger Steve

You probably should consult a lawyer, but the usual procedure in my area is that you post an ad in an "official" newspaper declaring the object abandoned and declaring that it will be sold for storage costs if not claimed within a specified time. Number of days that notice has to be published, and days you must wait, are usually specified in some law or another, that the lawyer could cite for you.

After that, you should be able to apply for a "lost title," citing the "publication of notice" and "failure to claim" in the application.

In lieu of, but less safe than, consulting a lawyer, the people who run "temporary storage sites" encounter this quite regularly, and should be able to give you a "non-professional" rundown on the procedure(s) they use.

In a few places in the US, you'll find a landlord-tenant law that includes "abandonment" clauses that likely would be a safe enough procedure. You probably can find the applicable ones, if they exist, with a bit of Googling.

Suggestions only: IANAL.

John