One thing I have learnt over the past 1.5 years since being on DNTrade and being interested in buying domain names is that value comes from quality generic names.
Buy less hand registered names and focus on good names from the aftermarket platforms. You will pay more for good domains but if you develop them they are worth the investment.
You can pick up some really great names for $500 - $1000 or even less if you're good at negotiating. Having said that still keep a look out for hand registrations, especially in evolving markets and new industries.
I'm not good at appraisals but if you can sell one of the domains you have listed for $150 you have not necessarily wasted your money.
I'm horrible at this! How do I value a domain?
Three letter domains are keepers right? I've got a few others, all letters, no Z's or Y's and pronounceable.