Reg fee in my opinion. Good seo costs a lot of money. A seo company would never use this because it will make them look bad. The only thing I can think of for development is a blog or an ebook but there are hundreds of them already.
You can get around $30-$40 perhaps but develop it more maybe into a SEO blog. That would be nice. Disappointed? Don't be. See this domain. According to checkpagerank.ws result Its a PR3 , 3 years old and has Alexa rank 69K. And its also listed in Google Directory! See whats its name Goodluck and make that website as your motivation p/s- Don't forget to use CPR to always check your site info..lol..