I heard that fixing oil leaks for the Boxer engine is expensive, so I just keep adding a little oil as I go. Now I also have a blown head gasket. Burning anti-freeze smells bad.

changed spark plugs at 90K mi and noticed oil on outside of spark plugs and spark plug wires, cleaned off oil at that time , spark plugs covered in oil again at 120K mi, oil leaking from valve cover gasket onto plugs, need to replace valve cover gaskets at considerable effort and cost due to access, plan to check and clean off oil every 20k mi, oil will not evaporate or go away unless removed and otherwise will build up and cause engine plugs to misfire