actually coins.com should be a 2nd tier domain name, a key word in a large industry
1M for coins.com
1coins.com should be 5 to 10%
now it would be hard to find a major coin dealer who could afford the 1M for it, so if you owned coins.com you should start a coin business and see how much the site makes you
you could easily make a 100K a year off it as a small business
then you sell the business with the domain name for 1M