Be careful! When searching for domains, it might be tempting to, for instance, buy (if it were available) and then try to sell it to McDonald's. The logic here would be that they own the .com and wouldn’t want anyone to own the .net and use their name, right? Also, it’s a big name so there’s gotta be a biiiiiiig payday comin’, RIGHT? Wrong, and wrong.
I have an interesting twist on how I have done it in the past. I will buy a domain and use it as a development domain for blog posts and things of that nature. Then over time it will gain DA and PR. Then I will sell it off and buy another development domain and start the process over. Not quite the process you mentioned, but it works. People will link to the development site to show things off as well  sometimes, so that helps.
Domain names expire when someone decides to stop renewing it. They may not be available to register immediately. We update the search index every night, so some names may already be renewed or re-registered. Some may become available in a few days. Some registrars, like GoDaddy, will let you buy a name that one of their own customers expire immediately. When you find a name you like, just click on it to try backordering the name!
it can be profitable,i'm selling domains and i can tell you that all providers loose money selling domains,we compesate it with  hosting plans but if you look just domain selling where providers buying domain for 7$-10$ and selling it for 0.99$-5$ ...well like say we compesate this with web hosting plans and other services,also on when some one renew domain but since even renewal is done mostly using cupons...than giving free domain with web hosting is best solutions.Well like i say it can be profitable if you want work with domain,buying domains for 0.99$ and than work with it and you can earn nice money.
We do not only have Expired Domains, but you can also find lists of Deleted Domains for a lot of TLDs. Deleted Domains or Dropped Domains are available for registration and can be picked up for just the normal regfee at your preferred domain registrar! All Domains have the typical SEO relevant data, like Number of Backlinks, Birth Date and a lot more. gathers all the information you need to find good Expired Domains that are Pending Delete and you can Backorder. Depending on the domain extension you can search through thousands of domains every day before they get released to the public and pick what you like. currently supports 449 TLDs. From the classic gTLDs like .com, .net, .org to Droplists for ccTLDs you can only find here and now we even support some of the best new gTLDs like .xyz and .club.

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.