The advice we would offer when looking for a roof cleaner in the north west area would be to ensure that quality products are being used. There seems little point in paying to have your roof cleaned and then not having the proper treatment applied to kill the biological growth
we have heard stories of people even trying to fool customers and merely applying water. Ask what product they use , ask to see properties from a previous season check their reviews. It all helps to get a reliable company on board
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