Look for a "non-gutter company" person. 
like a handyperson. . The "gutter company people" don't want to deal with fixes and/or adjustments once they have installed and a month or so have passed. I called the "popular" company who did ours to get one adjusted (it was slightly sagging) and one small (6') gutter added and was told "around 3 months". Then I called another who I didn't do business with and they never returned 2 calls. I finally got a hold of them and they said "only for our previous customers." Finally did the 6' myself and the long (I guess 20'+) is still a bit off.