We live in a 1907 brick home made of white brick. We hired an experience workman this summer to do tuck pointing and also to clean the front of the house (he said he'd use a mild acid of some sort, I think muriatic acid). Most of the cleaned bricks looked good, but some sections were stained (burned?). He has repeatedly tried to remove the burn without success using vinegar, baking soda, a power washer and perhaps other methods, and some of the bricks are now defaced but the staining/burn is not improved. He agrees with us that it's time to seek a second opinion as he has not been able to fix the problem. Any thoughts on whether the damage pictured here is repairable, or if we're down to either trying to find matching bricks to replace all of these or painting our house?