In the past, expired domains were used as part of black hat SEO in order to generate backlink sources quickly and easily, and this practice is still used somewhat today. Getting links in this way is not a recommendable practice. All relevant search engines work nowadays with highly complex ranking algorithms, which can no longer be outsmarted by these link networks.
Thousands of domain names expire every day. The reasons are different. Some owners forgot to renew the domains, some just don't want them anymore or they moved on to other projects. For most people these so called Expired Domains don't have any value. They just see a bunch of Domain Names someone else deleted and move on, but for the people who know about SEO or the value of good Backlinks, Expired Domain Names are money just waiting to get picked up from the street. The only problem is to separate the good ones from the bad ones. That is where ExpiredDomains.net comes into play.
There are currently two main types of domain speculators: those that buy domains, build sites around them, and then flip the domain and accompanying website, and then there are those that buy and sell domain names without web sites attached. While both can be very lucrative businesses, the second type is much easier for novices to learn, and as such, shall be the topic of discussion for this article. 

Multiply that number by the hundreds of potential variations we got from the Google Keyword Tool and NameBio, and you’ll brain will be buzzing with ideas in not time. Of course, not all the 1,300 currencies will boom, but if you bet on the right ones and take early action, you can get your hands on some very solid domain names. You can repeat all of this for almost every industry imaginable. Use a seed keyword on Google Trends and the Google Keyword Planner then just let the data guide your journey from there like we just did.
Surely if you purchase a domain (domain1.com) and redirect it to your existing domain (domain2.com) you expect to loose all ranking for domain1.com. If 301's are used then the objective is simply to pass on authority, not dominate the search results with 2 domains. If you want to keep domain2.com in the index then you would take Rebecca's option 2 or 3.
Review Web Archive’s versions of the website: Examine the website’s history and how it looked like using the Web Archive. What was it about? What did it offer? This is useful for a variety of different reasons. It could inspire you as to who a good potential buyer might be (by analyzing the website’s content), and it could also signal some red flags in case the domain was being used for anything shady.
Also with the domains, a name which can be cheap for one can be worth gold for the other. Permute the letters in your domain name and try contacting and eventually selling out to organizations that run under those names or contain the letters within. Companies would be keenly interested in buying out the domain names that matches the product's name. Hint : Look for companies on LinkedIn
When I first started online, I'd register domains that I thought I could develop and sell at a later time. After learning my way around the cloud, I realized many of the domains I'd registered are pretty much useless, or so I thought, and I let them expire. Come to find out several of these domains have been picked up by parking sites and are being offered for sale for thousands of dollars! Now I'm not saying they're actually selling for the asking price, but I learned my lesson. I never allow a domain name to expire. I add content to it, backlinks, some AdSense and try to sell it for something.

Listing on domain marketplaces: This is the most common route. You should, however, acquaint yourself with each marketplace’s policies and fees before deciding to work with them. For example, Sedo’s commission starts at 10% and BrandBucket prohibits listing the domain anywhere else if you’re selling with them. Here’s a list of the most popular marketplaces (in no particular order):
That’s it for deleted domains which you can just pick up by heading over to your favorite registrar and registering it right away as long as it says, free and green here. If it says registered it’s obviously taken. This is obviously a cheap way to get some great links because let’s say, you know, this site we saw is not bad. It doesn’t have page rank, but that could be just because there was no content on the site. If it has a solid link profile, you can be sure that the page rank will come back and you can pick it up for about $10.

Granted, it is not bad information, however, if EVERYONE rushes to namejet and signs up, the only people that really benefit are namejet 😉 The increase in competition means there are more bidders in the pool which will likely increase bid amounts (because the newcomers will not be able to ascertain a “true value” as much as a “pro” flipper would). The result is a lower profit margin as the method becomes saturated.

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.
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.
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