I've been on both sides of the transaction. The best advice I can give you is do a search on ebay for your exact phone: White, 32 gb, Verizon, AppleCare+.
The Verizon iPhone is GSM unlocked so definitely list Factory Unlocked in the title in there.
There's an option to show previously similar "Sold Items". That's where you can get a feel for what your item really sells for.
I usually don't list on Craigslist just because the flakiness factor. I like eBay but it costs you 13% in fees, but as a result, I don't have to worry about the buyer flaking on me by not showing up or trying to haggle on the price after the fact.
One other thing I usually do is Buy it Now. With that, if you go into Buyer Requirements, you can set a few parameters that should help you screen out some potential deadbeats. It allows you to block certain users if they have feedback ratings below 0 or any unpaid transactions within the last 6 months.
Then when you send the item, try to take some pictures of you packaging the item, the final package, and get insurance and delivery confirmation. Also get a picture of the IMEI/ESN. This may help you in case you the buyer tries to pull a scam on you by switching phones.