First flat buying: brochure vs reality check

Delhi projects ki amenities listing toh ek joke hai, seriously. New DS Apartment mein bhi yehi scene hai kya? Brochure mein swimming pool aur gym kaafi high-fi dikhaate hain, but possession ke baad kya sach mein usable hota hai? My parents keep saying check maintenance charges vs actual service. Ab samajh nahi aa raha, kya expect karun?