So I have been in the house for 30 years, the house was built in 1965 and I believe these are original. Over the years we have had trees fall on the house and the gutters need to be replaced as realignment was gone along time ago. This is an industry full of scammers around here. What should I be looking for in a good installer? I probably want wider..maybe 5"? and need a good guard as we are surrounded by oak trees. Any off the shelf product only resulted in weeds growing out of the gutter in a few years and overflow. I am prepared to hear that some of the backer boards might need to be replaced.