OP if they had you fitting, refitting etc under testing bed conditions fine but on your situation you were used as slave Labour

I’d ask for a refund and have a read of this instead.
http://www.pavingexpert.com/home.htm
Fwiw, I’d say they’re definitely having your trousers down, even so I’ve got to quite admire them, just for their sheer cheek! 😉

Agreed pocketrocket, I’m on the phone in the morning getting my money back, bloody annoyed about the 2 days I’ve wasted though!

My next business is to set up a CrossFit gig, let’s call it builderFit. Charge 100quid a month for unlimited access to job sites where you get to carry materials, dig holes, mix cement.
No different to what CrossFit offer except something productive actually happens.