Our 12” pine D-log home was stained with Sherwin Williams woodscapes stain followed by two coats of permachink lifeline advance clear coat almost 4 years ago (new build) and is starting to fail. What is the best approach to redo the failing areas? Do I need to totally strip the finish and start over? A Cobb blasting company recommended that I blast and restrain the whole house with their 4 coat oil stain for 30k, help!