A visitor went through all 6 pages and still never learned what a window costs
What it costs the business. The first question is always "how much does it cost?", and the site has no answer to it on the home page, in the "About" section, or on the contacts page. Nobody buys a window or a door on impulse: people compare several manufacturers and set aside those who don't name a price, because silence reads as "expensive" or "we'll haggle". Only a minority will take the step of writing to ask; the rest will go to whoever showed a price, and you will never know about these people.
What we do. We add a "from and to" price range for the main items: windows by profile type, balcony units, entrance and interior doors. Next to it, a short explanation of what drives the final figure: dimensions, number of chambers, hardware, glazing unit, installation. The lower bound does not commit you to selling at that price, but it filters out those who clearly can't afford it and saves your managers' time. This usually takes a day or two, copy included.

