Builders will start very nice and polite but ramp up to aggressive, dismissing your words, very quickly. Read your contract carefully and if you can spot a clause that supports your position quote it to them while they stare at you open-mouthed or go to their car and drive away. When you go into contract, write any additional conditions or definitions you require onto the document and have all parties initial the changes prior to signing. This will get the judge's attention and probably curb his decision to your favor when/if the terms are violated. Tie any variance from the plans or quality of work issues to definitive monetary deductions from the contract price. Let the suffering begin AND (hopefully) END at the time of signing. $$$$
The best is to have an attorney representing your interests, with experience in construction, review the documents prior to signing or simply write your own contract. But if the attorney seems loathe to modify the existing contract language, walk away from him. He probably works FOR the builder in his real life. $$$$
You can also take a small demo hammer and a camera when inspecting during construction. When installed/framed walls don't suit you and they don't seem to want to make it right, photograph it and just knock it down or put a hole in it. (You may want to take a burly friend with you during inspections.) Once the finish, trim and paint is dry you're pretty much going to own it whether you like it or not unless your attorney gets involved. $$$$
Good luck with these criminals who hide behind "conventional" wisdom, standardized contracts and an "I know construction and you need me" attitude. They are NOT your friends. They are persons scheming to succeed in a cut-throat business where the difference between their profit and a devastating loss could be as simple as an unlucky weather event, materials delivery failure or a careless subcontractor who can never seem to speak English when discussing serious issues. Their go-to position in the case of customer dissatisfaction is absolute denial. The cost of any generosities they may seem to show you are already covered in the contract price you pay. $$$$