I would like to apply my own SSL Certificate. How much will it cost?

There is a one-time setup fee of USD$30.00. The actual price of the SSL Certificate will vary by different Certificate Authority:
Thawte http://www.thawte.com - USD$125 for first year, USD$100 renewal
VeriSign http://www.verisign.com - USD$349 for first year, USD$249 renewal

3TEC.COM also offers GeoTrust SSL Certificate at a discount rate.