How long does something have to be in my possession until legally it can be claimed as mine?
You need to check your state laws about abandonment and whether you have to keep it safe or you have to give a formal notice via certified or registered mail before the law indicates it is yours. In tenancies for example, the landlord would have to keep it between six months and even a year in some states. The best option for you is to take the time to research the abandonment or escheatment laws in your state and then see what you must do to comply. If you do not wish to keep the item or items, the next best solution is to contact a mutual friend and arrange via email between all three parties to drop it off with the friend and have the ex pick it up.