Above you provided great information about buying and selling domain names. I have been to many blogs about the same and I have read the people make millions just by selling domain names. It's a process that one needs to learn with time and can give a good earning by reselling the domain name. The business is fruitful but one needs to read, understand the value of a domain name. Buying every domain name is a waste of money. One must see the future potential growth for that particular domain.
Get appraisals for your domain names. When selling, you will want to know what kind of price you should expect to get for your sites. There are a variety of websites that offer free appraisals for valuation. This includes larger domain auction sites such as Sedo.com, GoDaddy.com, and DomainIndex.com. These of course are only estimates, but they can give you a good idea of what certain domains might be worth.
I have some pot related ones I've purchased recently that deal with the manufacturing of hemp like hempmfr.com, hempmoulding.com, hemp-textiles.com, hempecofuel.com etc.  Some of the older domains I've been sitting on are ones like internetpot.com, califunk.com, cafunk.com, caedibles.com, 1tokewonder.com, govherb.com, grasspeddlers.com, pot-megastore.com, usgov420.com etc.  Another interesting recent on I've purchased is Dogparkdates.com and dogpark-dating.com. Do any of these seem valuable in your eyes?
When you see one that looks pretty good you can just click on the bid button and you’ll be taken to Go Daddy Auctions which shows some more information about the domain bidding process, how many people have bid, the traffic potential per month, the price which is now $12. How much time is left? You can make a bid. It’s based on the link profile and it’s relevancy, authority and your budget. This domain looks like a good bet for you.
I don't necessarily agree with some that dropped domains don't have value for SEO purposes but either way one thing you can do is to check out our tool for finding auction domain names (the tool has a database of domains available buy from GoDaddy and SEDO and also give additional SEO criteria to look up for the domains like backlinks, Compete data, CPC, Google stats, Alexa stats, etc. and there is also an option to schedule auction domain alerts so that you can be notified via email if a domain name meeting criteria you specify gets put up for sale) or you could use our tool fo domains dropping soon that shows all domains dropping in the next 5 days that way you can be ready to snap them up right away.
As people who normally use internet only to check emails, shop, tweet, upload pictures, update facebook status or conduct some business, a large majority of us remain oblivious to the domain name and domain flipping industry. So, when we do decide to venture into it for some reason, it is only natural for us to carry some commonly known myths associated with it. It can also be easier than building a website from a scratch. Although with easy to follow guides relating to how to create a blog – many are choosing to go down this route and add value to their domain names rather than selling undeveloped.
Yes! Selling domain is an emerging trade and no wonder if it can develop into an exchange. www.DomainX.org has been initiated with this view. There are some good ideas in the comments regarding which names to buy and how to grow their value. However one must not forget that it also involves a recurring cost (annual renewal) and keeping many of them might become difficult if you are not really selling at least a few to cover it. Enjoy free listing at DomainX.org.
Length: This is pretty self-explanatory. Generally the shorter the domain name, the more valuable it is. This difference in value decreases exponentially as the name gets longer, though. For instance, the difference in price between 3 and 4 letter domains are significant, while the price difference between a 7 and 8 letter domain would usually be much less significant.