I agree with the others on tossing opened items except condiments.
However for the never opened or used items I simply check the expiration date. If the grocery store would allow a return within their return period of an unwanted unopened unexpired item and stick it back on the shelf then I don't see the harm in keeping it.
For the opened items (which although gross is still technically perfectly good food in most cases ) i am lucky because I have a longer-term tenant who started as an Airbnb guest that I am now helping while he is in school. He came from a country where a lot of people are very poor and therefor he was raised not to waste anything. So he gladly takes any and all of the still edible food (checking if it's still good first of course) they happen to leave behind.
I wonder how hard it would be to ontact the local homeless shelter or see if there is any programs with your local government or church would possibly take unspoiled items off you hands and hand them out. Or you could always had it out to them personally .
Lastly I want to share a tip I found works for saving money on condiments: so after telling the guest they can use any and all condiments (so they don't have to buy them all themselves only to have to abandon it if they can't take them with them for space reasons), I ask the guests to just replace that single item with the same thing or an item of the same approximate value. This also helps because most guests will forget to tell you what items you ran out of during their plus you dont have to task them with it either.
Hope this helps ! Cheers - SJ
