Builder-buyer agreements are designed to trap you

Honestly, I completely underestimated red flags in builder agreements. Checking an Anant Raj Group project near Sector 14. Builder said 2 years for possession, par agreement mein 18-month grace period tha. Matlab, 3.5 saal tak lag sakte hain. Is this normal practice? How do you spot these hidden clauses? Ab samajh nahi aa raha.