Most are sort of regional, what region are you in?
eg I used Saltire for our mini barn stables, they were very good. One thing I liked (having lost £000s by a fraudster running an agric barn company) was that they only asked for 25% up front, the rest wasnt due until the whole thing was complete. This gave me confidence and also a company that does that is clearly not anticipating massive moans meaning customers disputing on 75% of the money. But they are based in Fife, Scotland, which might be hundreds of miles away.