That sounds quite high, based on my daughter's recent experience - a lot of her costs were for scaffolding, which I assume is not needed for a bungalow?
Hers (a small house - roof probably smaller than a bungalow) took a few days, but these were spread over a couple of weeks because of bad weather. They can work in the rain, but not if the materials they are using will be affected by being wet (cement or whatever they use). There was one 'main man' with a couple of labourers brought in as necessary, plus the scaffolders, who were hired in rather than part of the company.
He did take videos, and has given a full guarantee, as well as coming back to check things like guttering and making necessary adjustments. I'm not sure of the exact figure, but it was somewhere around the £10k mark. She lives in the NW, if that makes a difference.