I have used tradesmen from Facebook. SO variable, good reviews are no judge of quality.
I would do as Ooops said and go on personal recommendations, OR search a long standing company online. I have used two sets of roofers. One, awful, did a dodgy job and expensive for what they did (I didn't realise it before). The second, a company in the area for over 30 years, VERY reasonable price. Fixed the problem first time with no fuss, bother. AND worked very quickly, but completely solved the problem.
Searching for recipe in Supercook magazine