What I like to do is sort by DP which stands for domain pop, and this is basically the number of linking root domains. So, BL is the number of back links. As you know that can be somewhat misleading if they have a lot of site wide links or multiple links from the same domain. I like to sort by domain pop. What that does is it brings up the sites with the most amount of referring domains.
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.
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.
Just because something is legal does not make it ethical. While things that are legal can and often are ethical, there are practices like domain name flipping that are not ethical. Buying a domain name without intending to use it to make profit creates an unnecessary industry which costs people money and reduces general productivity and economic growth. This is the same with all practices that cost people money but do not contribute any value, most notably corruption. If we eliminated such practices our economic growth increases and general wealth is increased because our money is paying people for things that add to our lives and our communities. This does not. Evessariky reglect badly in people who choose to engage in such practices, but is a result of regulatory failure.
I did this last month, snagged a great domain that no one else found and got it for $69 because I waited until the last moment to place my pre-bid. Flipped it within a week for a little over $1,000. And probably could have gotten more if I sat back and waited 6-12 months, but a bird in the hand… (plus I like to keep turning over inventory and maintaining cash flow).
So how do you develop that instinct? NameBio maintains a database of over 500,000 historical domain sales (as of writing this post). They have interesting filtering features by which you can narrow down domains by price range, date sold, keywords and more. Simply sifting through the listings on NameBio long enough will quickly develop your domain appraisal “instinct”.