You might want to look in Mudcat's Tech: threads and see if there is anything about the microphone maintenance. People talk about selling instruments every so often, so find an existing one or start a new one (above the line) and see what advice you get.

If you have things that fit their list of acceptable donations, the Salvation Army will send their truck out to pick up everything. Take photos and get a donation slip from them and take it off of your taxes. (Schedule A) - and if you need, you don't need to take all of the donation credit in one year. Or you can add a couple of years' worth together (check the form instructions, they tell you about this).

If you are on facebook, there are local selling groups that are apparently more reliable than Craig's List.

My score isn't 500 at eBay, that's the next target. I'm somewhere around 300. There is the "local pickup" option on eBay, so you might want to try listing some items that way, and have a friend come over to the house to be there when the party arrives to pick it up. Get the PayPal payment before they come over, to be sure they're for real.

I hope this helps!