Tinning a PCB

[Dj Task Manager]

Hi Yall, I need to tin coat a large (20cm sq) PCB Im making.  It needs to be tinned because it is not only a circuit but part of the instruments interface and thus needs to be resiliant and conductive and not oxidize.  I thought I'd fish for some advice on the pros and cons of electoplating, liquid tin / tinnit and tin crystal rub stuff before investing as it seems it can be quite costly...

Cheeeerz!