You all know that Google PageRank is the formula that determines how important a webpage is. According to it, sites with higher PR rank higher and have more authority than others with a lower PR.
Normally, when someone is looking for a domain to buy, he or she is interested in getting one that has a page rank. Finding such domains was rather difficult not long ago. Can you imagine what one had to do in order to find an expired domain with a PR? It used to be a long and boring if not tiring process. First you had to download a list of thousands of expired domains, select the ones that were interesting and feed them into an automated PR valuator to see which of them still had a valid PR. Too much work for nothing as very few came to meet one’s need.
Fortunately, several new websites have been launched to make this a lot easier for anybody who is after expired domains with PR. Expired Domain Up! Is one of them, probably the best so far as its database is updated every day and there are several filter options you can choose from to ease your search and find only what you really want to. The system will also show you exactly where to purchase those domains and direct you straight to the appropriate auction.
What is PR determined by? Well, PR is given by both the quality and the quantity of the back-links that point to that domain. Thus, it is very important to build a high-quality website and take care of its content on a regular basis (updating it as often as you can). You also need a number of very good quality links (preferably not reciprocal, because one-way links are better PR boosters than reciprocal ones).
A very serious problem that usually arises when you are on the verge of purchasing an expired domain with PR is the fear that the page rank of that domain is not real. I think you are entitled to be cautious. Not even the Google system is a sure way to validate page rank and you might buy less than what you want at a very high price. When sellers advertise their domains, they will not always tell the naked truth to the potential buyers and there are quite a number of con artists out there on the web. In order to be sure that you are buying a domain with a real PR you should use one of those fake page rank checkers (sem-faq.com and seologs.com are two of them) not a regular checker. They will determine the PR and will also tell you whether it is a fake one.
Next you had better check the back-links too. Most expired domains still hold their PR if they have top-notch back-links that are relevant to your search. However, webmasters usually remove back-links if the content is no longer relevant. Besides the back-link checker from seologs.com, you can use iwebtool.com which is also very reliable. You may even use both if you want to feel safer.
There is one last check needed before purchasing the domain that you want so as to determine the validity of the PR. Type: info: [the name of your domain] plus extension but not the www. If you get at least one exact result in the index, there is a good chance for the PR to be valid.