I wouldn't be taking advice about construction cleaning from a website who's primary goal is to sell quoting software. The person who wrote that probably hasn't ever done a construction clean in his life and the things mentioned in that article are extremely generic.
I also agree that there is no replacement for experience, so my recommendation would be to first get a job doing construction cleaning, once you learn the ropes then start your own business. In my company, we have house cleaners and builders cleaners, their skill set is very different.
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