Before Buying New Domain Always Check Whois History,
1- Domain Status
2- Registrar History
If even you think the domain is new and available be sure look at http://whois.domaintools.com domain status,
If its Show "Deleted and Available Again" means someone has used this before but don't know why he didn't renew it.
Registrar Status Help us to know: that domain is penalized or not? if more than 2 registrar you found means people didn't get success and didn't renew the domain and it becomes available again.
Best thing is always register domain which shows "Domain Never Registered Before" to get success with own hard work.
This tip is just for registering new and fresh domains only, Not expired domain for expired domain sure domain show deleted and available again but for penalized or not you need to check yourself by analysis domain.
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