Just my 2 bobs worth on this subject. Being involved in the insustry as a plasterboard seller and contracting for 30 years. I find the biggest problem with the industry is mistrust.
If a builder feels the client is being to "nosey" or being very pickky etc or showing doubt. the builder is imediatly defensive. Now uncertain of their clienst motives and if they will get paid or end up in dispute. They take protective steps adding fuel to the clients concerns and bingo you have a dispute.
This works both ways. I have seen Builders and Clients get hardend attitudes over the years. This is also partially due to the information availale to people these days. We can normally tell if a client has the potential to be difficult and will avoid them.
The answer I think for Clients and Builders is to feel comfrotable with each other from the outset and have some guidlines on how to deal with issues that arise.
If you have any doubt at all don't do the deal.
Cheers Rod Dyson Plaster Brokers