I agree that you can find something used and you can usually save a lot of money, but as the point made above said, it takes time and sometimes you need to compromise on type and size. In my limited experience bents don't depreciate like your typical bikes so you probably won't get one for next to nothing.
You might want to find something less than ideal and then shop. Your 'less than ideal' bike will still be worth something when you find just what you want.
I've never had a TW-bent bike but I'm hearing very good things for the most part. Also, if you are looking at trikes you might want to look at WizWheelz as they have a trike for 1300 and you might find a dealer near you.
One last thing, if you find what you want on line (ie BROL classifieds) please read the 'don't get scammed' thread on that site and things to watch out for here and and elsewhere. It might save you a headache or two. Granted most bent sites are frequented by very nice people but all it takes is one.