In the grey hat SEO world, the thought is that you can take a domain that is keyword driven, do a quick optimization to get the site ranking, and sell it off at a profit. It could, and does happen daily. How much time is invested in optimizing a site to get to page one, vs how much the site will sell for? (remember that quote at the beginning of this article?). Let's put it into simple math:
Domain investors build a portfolio of valuable domain names, and attempt to sell them at a profit. Both Sedo and Afternic offer domain marketplaces (also known as Domain Listing Services, or DLS) for investors to advertise their domains to potential buyers. Once the seller and buyer agree, the aftermarket platforms then facilitate the purchase and transfer of the domain(s). As an Enom customer, you’re entitled to list your domains for sale on Sedo, Afternic, or both at the same time. Get started

The first is the link profile I and actually took this example because it looked like a pretty good choice. It’s from 2003. It has some links, some age and it’s in DMAS and looked at the link profile in DMAS. So, you just copy and paste the domain,  the home page it to here, click on the search links button and this will show you all the links to that site.
Parking: While your domain is just sitting there waiting for its new owner, you might as well take advantage of it. Parking sets up automated advertising on your domain so that you earn money every time someone views/clicks on an ad. This could be especially useful if your domain is an expired one that’s already receiving traffic. Services that offer parking include Sedo, GoDaddy, 1and1 among many others.
Don’t get me wrong, I’m not saying marketing your domain is not important. But, if you’ve bought a bad domain and you do (and overdo) everything laid out in this section and more, it’s still very unlikely that it would sell. It’s like spending car flipping and spending a huge amount of money, time and effort perfecting a car’s paint job, except that this car’s engine is completely fried. You’ll never be able to drive it anyway, no matter how awesome the paint job is, it’s irrelevant.
What is a domain? Despite this word being mentioned so frequently, it’s often unclear what the functions and structures of domains are. Knowing the hierarchical structure of the Domain Name System (DNS) is fundamental for anyone working in IT or in any online industry. We explain the difference between top-level, second-level, and third-level domains, and how you can benefit from subdomains that...
The practice of exploiting misspelled variants of popular websites for personal gain is known as typosquatting. Users who incorrectly enter URLs into a browser’s search bar may be getting more than what they’ve bargained for and end up on a squatted domain. We’ll show you how typosquatters exploit the simple workaday mistakes of internet users and how website operators and their visitors can...
Using the keyword search feature you’d also be able to familiarize yourself with how much domains typically cost on average in a certain industry or niche. Even better, they have an addictive little app called “The Domain Game” available for iOS and Android. They basically give you a domain and you try to guess whether it sold for three, four, five or six figures. You get points for each correct answer and lose points for incorrect ones. You do this for a while and you start to see patterns. Your brain starts connecting the dots and you get better it. Now you’re ready to go out there and scout some domains!