If you buy a domain from a 3rd party, the backlinks are valuable.  I always wait a few months before redirecting, so just set up a quick minisite until two page rank updates have passed and then go ahead and 301 redirect.  However, it seems that you'll get the link juice from the back links, the anchor text is ignored by Google.   Buying a domain at Godaddy TDName expired auctions, seem to not count as a dropped domain if you immediately set up a mini-site.
It's ranking high today! What could be the problem? NO. JUST STOP. Unless you know the entire history of a domain, you may be setting yourself up for failure before you begin. SEOs (and business owners) use a variety of tactics to get a site ranking high in search results. For some of these methods, we'll just call them "questionable". These methods could include everything from buying links, overuse of directory submissions (non-industry related), duplicate listings, poor quality backlinks, and guest blog comments.
You can’t tell us (with a straight face) that aged dictionary word .net and .org domains won’t sell easily. The .net extension is technically OLDER than .com, and holds an equally intrinsic value to that of its .com counterpart. These LLLL .com’s that are just letters slapped together may be cute to look at and easy to sell, but in the eyes of Google, ANY aged domain that makes sense (i.e. a dictionary word) is going to be much easier to rank for than some acronym or hodgepodge .com…and at the end of the day, that holds more value than whatever society sees in these nonsensical “wqij.com” names.
I've seen some people comment about losing the link value of domains that have expired and picked up, but what about non-expired domains?  Let's say a competitor is going out of business and they still have a year or two left, and we buy their domain and site.  Is there a risk changing registrant info and registrars, even if I keep their site up and mostly the same as before?  I was under the impression that I'd want to keep it under their name so as not to hit the uber-reset button on the domain's inbound link value.
There is always a learning curve in buying domains with the purpose of reselling them. Don’t hesitate to ask a lot of questions to those who went before you, participate in forums such as namepros.com and dnforum.com, keep abreast of industry trends via resources like domaining.com, and reach out to the Afternic and GoDaddy Aftermarket support teams.

Many top-level domains, or TLDs, out there have the potential of being sold at top dollar rates. Gone are the days when domain names with ‘.COM’, ‘.ORG’ and ‘.NET’ were known as top-level domains. Newer domain names with ‘.US’ and ‘.IO’ are also worth their weight in gold. All you have to do is conduct thorough research in order to find all the good domain names you can park.

Once you’ve settled on some domain name ideas, you can head over to a bulk domain search tool such as DynaDot’s to mass check all the names against different TLDs. When you’ve found one (or a few) good candidates, you can simply go ahead and register them for approximately $10 each. The next step would then be to market them. Then finally, it’s a waiting game.
It’s also not so easy to manually re-register. This is due to backorder providers which are paid to keep an eye on expiring domains over a certain period of time and then register them for the customer as soon as they become available. Promising expired domains are therefore usually sold before they have a chance to be put back on the registry menu for the public to look through.
Sellers should also learn to identify premium domain names. Dictionary names are premium domain names. Domain names with dictionary-singular names are the hottest on the Web, and buyers are willing to pay a lot to purchase them. Names, such as search.com or askme.com, will get buyers more easily than long domain names. It is also important to note that unhyphenated domain names have more value. Even product-related domain names also can enable sellers to earn substantial profit. Once a seller has a certain degree of knowledge about the domain, he can start searching for buyers.

You can’t tell us (with a straight face) that aged dictionary word .net and .org domains won’t sell easily. The .net extension is technically OLDER than .com, and holds an equally intrinsic value to that of its .com counterpart. These LLLL .com’s that are just letters slapped together may be cute to look at and easy to sell, but in the eyes of Google, ANY aged domain that makes sense (i.e. a dictionary word) is going to be much easier to rank for than some acronym or hodgepodge .com…and at the end of the day, that holds more value than whatever society sees in these nonsensical “wqij.com” names.
Many non-savvy internet users may not even be aware of the existence of other extensions. That said, because there are many new extensions popping up every now and then, you can often find amazing one word and 3-letter domain names with these new extensions that are otherwise almost impossible to find unregistered in the .com world. Additionally, these new extensions are becoming more and more familiar to users every day, hence it's almost certain that their value will continue to increase as time passes and wider adoption manifests. 
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