Although, the benefits are many, it’s best to conduct an in-depth research before deciding to go for an expired domain name. Here are a few steps of research you should conduct before going in for the desired expired / to be expired domain name
1) Indexed Pages – You can find the indexed pages of the expired domain by using Google search operators. You can use the following to search operators to find any footprints left by the webmaster all over the Internet.
This will help you find all traces to the expired domain on the Internet. You will find backlinks from profiles, comments in blogs and if articles on article directories (if any)
3) Google Adsense Sandbox – If you’re planning to monetize your new domain with Google AdSense. It’s best to check if the the webmaster has not performed illegal activities and is ultimately banned by Google. A good tool to check for the Google AdSense sandbox is http://www.labnol.org/google-adsense-sandbox/
If the Sandbox is showing NO RESULT for an Existing/Expired Domain Name, probability is very high that the Domain Name is banned from Google AdSense Program.
These are some of the tips we could list down before going in for an expired domain, do let me know your inputs on what could be checked additionally.