CRE loaded 6.2 Hacked repeatedly

CRE loaded 6.2 8 We are being attacked by malware virus on the site, We need all our codes cleaned from malicious codes, the site secured with secured Admin area and image folder. We also need any other files which may be prone to attacks secured and patched. We are using 1 Database as a multistore setup across 3 domains. The other domains admin panels have been disbaled and yet the site is always hacked with a virus appearing in the browser. Worse still it will redirect the whole site to another unknown website, not linked with us. We are avoiding upgrading CRE versions, as we have heavily customised the site already. We need this work guaranteed, so that further attacks are not compromising the site. Budget $150.00 USD