Deckmasters

Quoted a lady her deck with paint on it the other day. She failed to tell me there was 2 coats of paint and in addition the deck had a primer on it called Kills. Have stripped the deck 3 times with HD80 and still have white spots of Kills on the deck. Has anyone ran into this type of primer before??? If so, how did you get rid of it...won't even sand off. This has literally been the deck from H***. Any comments would be greatly appreciated. **** :mad: