Cat Diagnostics System with leads

Hi All I'm Looking for a Cat Diagnostics tool to do the full range of cat machinery. We mostly run the GC range but I don't want to pay Cat prices. Just looking to read codes, set up and code new bits plus delete codes and so on. has anyone got a company/or diagnostics tool they use that they would recommend or know of someone that does Genuine fake downloads to a laptop with the leads Any help on this one would be spot on. Thanks in advance