Buying Domain for Blogging

I have eagerly to be succesful blogger. As long as I have done, Free blog is my choice. by using free blog, everyting is easy. The layout is easy usage and friendly user. However, many said that using free blog is commonly difficult to be maximumly monetized.
In that case, I try to have another blog, still use free host in blogspot but use paid domain. This domain for my new blogging is not new but used. There are some advantages to get used domain. they are publicly known and having longer age. From Search Engine point of view, of course, this is more lucrative.