Are you sure the resell value of 10-22mm is good? I had posted my 6 months 10-22mm on CL for two weeks and asking for 650 in bay area. No one offered more than 600 for it. In the last, I had to compromise the price 600 USD. 6 month lens for only about 75% resell value.
Well, there are multiple mistakes here. One, using Craigslist and being surprised that people low-balled you. If you're selling expensive photo equipment, go to a photography forum to sell it. You'd have probably gotten $650 pretty quickly from FredMiranda or POTN. This also makes the point, buy the 10-22 used from someone in mint condition, you'll save some money (say 10% off retail), and when you resell it, you'll have not lost that initial retail price.
Every lens, no matter what, is gonna lose 5-10% when its no longer brand new in the box. Only if the demand gets really high (24-70 for example) will a used lens sell higher than new. But, if the trade off of spending the extra $100 in this case is that you get a useful focal length for 2 years before upgrading, it's well worth the money