Query about builder doing some facias and guttering

A builder is doing some work for a grandmother in law. He is replacing guttering and fascias on a bungalow and putting a new plastic roof on the car port. In the original quote he stated he would remove 3 sections of tiles and remove and replace old felt. Looking at a section he has half done, he has only removed 1 section and cut about 8 - 12 inch of old felt away and replaced with a small length of felt to run in to the gutter, the old felt is fairly fragile. From what I can see non of the ridge tiles have been removed. Also they have a flat roof extension and when he quoted he stated he would remove the old felt lip and replace, he has not done this he has heated the old felt and refitted. As such he has left the old wooden fasica in place and nailed over the top. The bungalow is a 3 bed with dining extension, not massive. The car port is about 4 x 2m maybe a little bigger, snug fit with a car. Whats the average cost with replacing fascias and guttering for a detached bungalow? Any advice about things to check would be appreciated, I've got to inspect the work and pay the builder.

I would really appreciate some advice if anybody has any, I'm a little nervous about approching the builder when it comes to payment. Thanks in advance.