Service Not Received

I bought a flat in Ghazibad, hired an interior company for woodwork. They promised: 1. High quality stuffs 2. Bubblesheet to avoid seepage in future 3. Godrej or high end brand products to be used. I was not provided service on time, we have a seepage issue and found that they haven't used bubble sheet anywhere. Also instead of using Godrej they used local stuffs. I have paid round 75% of money. 80% work has been completed, now interior designer is pressurizing for full payment. I have suggested him to get bubblesheet everywhere, use Godrej stuffs and complete pending work. I dont have any paper agreement.