Under-construction projects: How to really check quality?

₹1.8 Cr for a 3BHK in Prestige City feels steep for under-construction. I'm upgrading from my 2BHK. Site visits pe builders mostly show finished sections, but real construction quality often hides. My current home had seepage issues post-possession. What specific things do you check for plumbing, electricals during under-construction site visits? Also, amenities like children's play area or clubhouse – how to gauge actual usability early on? Any hacks for spotting potential issues? Hope this helps someone.