Shopping for shelves for our office wall

Emma wants to redo our home office shelves, on the wall behind us when we are at our desks. Currently its a collection of folding shelf units and such we accumulated over the years, generally nice wood, but mismatched. We had gone to IKEA but it looked like we would spend $950-1200 for a system the way we wanted it. And flat pack furniture from around the world isn’t very green.
But then I saw this Modern wall system on Craigslist … Its a little rough and the seller wants way too much money, but its flexible and doesn’t rely on proprietary hardware like that old SCAN system I got in FEB …