If you are not careful with the service provider you select to work on your building, you could end up with more problems after removal than you started with!
Unfortunately, this industry is not regulated so there are some unscrupulous characters doing very average work in an unsafe manner.
If stains are incorrectly removed, then you may also have ongoing issues with salt deposits, rising damp and premature brick crumbling, and in the worst circumstances, structural failure.
When stains soak into masonry surfaces like brick, concrete, sandstone and granite it penetrates and soaks deep into the surface, like ink into chalk!
It takes a highly-skilled Surface Restoration Technician with experience and patience to draw it out with the right technology without eroding or degrading the original surface.