While there is no exact science as to what type of domain names will ultimately be worth the most, apart from the obvious short and memorable domain names, there are a few things to keep in mind
Avoid registering any domain names that could infringe upon the trademark of existing companies, whether or not you believe that the company will take action or not should not be considered. The last thing you want is to purchase a domain name that is unable to be sold due to buyers being cautious or concerned of building a website on a domain that ends up being seized by a company wishing to protect their identity.
2. Length of The Domain Name
It can not be said enough, that the length of a domain name, apart from the odd occurrence where you locate a lengthy domain name that still carries with it, a memory element, most of the domain names you purchase should be relatively short, basically consisting of two words.
3. Relevant and Popular Keywords
Does the domain name contain popular keywords that are used by those seeking out more information in search engines? If so, your domain name just increased its value instantly.
One of the easiest ways to determine whether a keyword is a common one is by using the free service available at www.SEOBook.com or www.Overture.com
4. Domain Development
When you analyze the available domains in your list, consider what each domain name could represent and be used for when creating a website presence. An example of which is whether the domain name is one that could represent a product title, or better served as a personal portfolio, a social community, a directory or perhaps a forum. While the purpose of the domain name will unlikely match your ideas when it is sold, by thinking of a clear purpose for each domain name will not only help you make sound choices during the selection process, but can also be included in the domain auction, as a way of passing on the ideas to prospective buyers who are considering purchase.
5. Existing Traffic
If you are purchasing aged or recently expired domains, you will want to determine whether there is existing traffic to the website or not, thus increasing its value. Organic, natural traffic sent directly from search engines is the best kind, however, backlinks from other websites are also very important to potential buyers.
An easy way to determine the number of backlinks, as well as page rank and other important information, is by visiting www.CheckPageRank.net where you can enter in domain names and retrieve useful data relating to the name itself.