Best Backflow Assembly Tested in Washington DC

I've had Durance provide plumbing services on a couple of occasions at various properties that I own. This time I called on Sat about a water pipe and water heater issue at a resale property I bought earlier in the year. They indicated their schedule was packed but would work to fit me in on the upcoming Monday afternoon. They came out as promised and quickly diagnosed the issues. They explained what was going on and offered me some options. Finally they performed all the required/ requested work satisfactorily. Continue to be pleased with their services and personnel.