The answer to 'how much to fix backflow preventer in Chicago' is that the cost can vary widely depending on several factors. Backflow preventer repair and maintenance in Chicago typically ranges from $150 to $500, though more complex issues could cost up to $1,000 or more.
The exact cost will depend on the type of backflow preventer, the extent of the repairs needed, the accessibility of the unit, and whether any permits or specialized tools are required. Additionally, labor rates in your local area can significantly impact the total cost. It's best to get quotes from multiple licensed plumbers in your Chicago neighborhood to compare prices and services.