You might be able to sell on ebay for $1800, but it will cost you $150 or more for fees. I'd ask $1775 on CL and be willing to come down to $1650.
Having the manuals, CD's and cables helps. Even a old 35-80mm EF lens might bring a extra $100 when bundled with it.
New MK II's are about to Drop to the $2000 level, so sell quickly while they are still $2269.
Ebay Fees on this item would be capped at $100. Now you do have to add in the PayPal Fees, which is $52 (2.9%) on $1800.
It is a wash on Craigslist at $1650 if you can get $1800 on eBay with a bigger market.
One of the best places I have found to move this gear is actually Amazon. I got more for my 18 - 135, 10-22, and 70-200 f/4 off of there than I did off of CL... Close to DOUBLE what the tire kickers on CL were offering.
Amazon pretty much does rape you with the fees, but after a week of tire kickers on CL offering $200 for my 70-200 F/4, or $500 on my 10-22, wound up selling 3 lenses and my 430 EX II in about 3 hours for pretty decent money after the commissions.
Also it can be a great way to split up transactions for those aware of the new IRS rules, basically the 200 / $20,000. If you are clearing out a bunch of gear on either site, it is easy to get the dollar amounts up, and then realize you have a ton of rinky dink transactions that might make you have to file for all those DVDs and CDs you cleared out at $4 a pop.