In 2009 a friend who had to move out of his house and needed a place to store a few items (collectibles, clothing, misc personal items and some computer stuff). I allowed him to leave his things in my house until he found a new place. Since then, he has been "traveling" for work and only been back in town twice. Since March of this year I've asked him repeatedly to remove his belongings from my home only to hear that he can't or has to make arrangements. I've given him "drop dead" dates twice via text and email as he has no permanent address- once with 30 days to get his stuff out and on 8/16 with two weeks and now I have not heard from him since 8/13/2011. Can I donate his belongings to Goodwill?
Tricky matter, all too common I'm afraid.
The problem is that you originally agreed to store his items--in many states that creates a situation where you have a duty of care for his goods.
However, is not indefinite in duration and you appear to have made good faith efforts to contact your friend and request he remove the items. If I were you, I would keep copies of all the emails, texts, voicemails etc. to substantiate your claim that you repeatedly contacted him and he refused to take care of his items. If you decide to donate his items, document what you donate, keep the Goodwill receipt to add to your documents.
A local legal clinic (contact your county bar association) might have volunteer attorneys familiar with Kansas law who can advise you on exactly what steps to take--perhaps involving the courts, against your friend as a further measure in protecting yourself from a later claim that you converted his goods (sold them for your own profit).