What to look for during an under-construction site visit

Been looking for a compact flat for almost a year now. Kids have moved out so don't need such a big place anymore. Selling our old property, want something manageable near a good hospital. One thing I've learned, especially visiting under-construction sites like Gitanjali Apartments, is ki walls aur plumbing fixtures ko bahut dhyan se check karo. Sales reps will only show you the model flat, but actual construction quality, like uneven plaster ya low-quality pipe fittings, wahi dikhti hai jo abhi ban raha hai. Cracks aur seepage issues toh baad mein headache dete hain. Also, elevator quality aur full flat power backup ka bhi puchhna. Yeh chhoti details bahut important hain, especially for older people. Hope this helps someone else who's downsizing. Any similar tips for identifying red flags during site visits?