If it's a Persimmon Homes development, take at look at the "Don't By A Persimmon Home" Facebook Group.
Generally, New Builds are a disaster waiting to happen. They are built to the lowest possible legal standards, and usually fail the majority of those. The "trades" are mostly hack jobs, done to deadlines. There is no pride or skill, just build them fast n cheap. If you go ahead with this, when you move in, take the bath panel off and let us all know what you find under there.
Think about this.
You don't have snagging companies for car sales, clothes shops or any other business. Even the development companies are admitting the product they are selling needs remedial work.
Would you pay 250k for a car that had to be taken back to the garage after you paid for it, to have all the broken bits fixed and other things added to it so it was safe to drive?
Also, New Builds will be in depreciate by a huge chunk the moment you exchange, because you now own a "second hand" home, so if the development isn't finished, the prices could vary significantly even for the "same" houses.
Pick any "New Build" estate and give it five years. The houses will be falling apart. Cracked and discoloured render, lose slates, dead lawns.
I really wouldn't bother.