Is $15,000 to install box gutters a fair price?

I am a first-time homebuyer and paid $15,000 for just box gutters. I am not pleased with them three months post-installation. I am wondering if the issues I'm observing are cause for concern. When it rains, the porch slopes, causing water to flow over the side very badly. Also, it looks like some water is sitting on the rubber instead of going down the gutters. There are numerous holes in the seams of the rubber, which I am concerned will cause severe damage over time.