How long does it take for someones property to be considered abandoned

These are always difficult questions to answer, because they turn on the intentions of the owner, which need to be inferred from conduct. The usual suggestion is that you give written notice to your ex-wife (by certified mail) of your intention to dispose of the property unless she retrieves it within a reasonable time (say, 30 days). Once you have given such notice, many attorneys will think you are as protected as you can be. This is not legal advice.