Acid Washing New Construction Brick too late

Does anybody have a waiver that they use when they get called in to acid wash new construction brick outside of the timeframe where it's feasible to get a good clean up of the mortar tags and smears? I'm getting burned on another job where they waited 3 to 4 months to call me in to clean. Repeated applications of nmd-80 and high pressure cleaning is only getting 90% of the mortar mess cleaned off, and the supervisor is calling us back again and again to touch things up. Besides, the project is in the phase where they are doing other exterior stuff like the parking lot so our access to the building is very hit or miss. I figure a good waiver would have absolved me of taking responsibility for their mistake.

I wish more people brought the brick cleaning subject up. I think single story offices and two story new construction here is .50 per sq.ft

Scrape it good before you start get that stuff on there pretty strong and it should come off good.Your application method is critical on brick.