The SMF 2 RC3 is a open source software and you need not pay for it, But the Theme will install through the SMF package, by following simple instructions, If you like to request that someone installs the SMF system to your site I sure someone here will be willing to help you. Some hosting Companies have this pre-installed the Version 1.1.11 so you can just upgrade it from there, you may want to contact you host first and see if it's allowed and if they can do it for you, or if you can do it yourself through your Admin Control Panel!
If you then need a custom theme G! or someone will help you with this!
regards,
Maxx