By the time the agreement is drafted, everyone is excited and wants to sign. That is exactly when to slow down. These are the parts that decide what happens if something goes wrong.
What is being sold
The full description: survey or flat number, floor, carpet area, parking, and any shared rights. It should match the papers you checked, word for word.
Price and how it is paid
The total price, every instalment, and what each one is tied to. For an under-construction flat, payments should follow construction stages, not just dates. Note what is not included: GST, stamp duty, registration, maintenance deposit.
Possession and delays
The possession date, and what the builder or seller pays you if it is late. A date with no consequence is a wish.
Cancellation
What you get back if you cancel, and what you get back if they do.
Clear title
A clause in which the seller declares there are no loans, cases or claims on the property, and takes responsibility if one appears.
This is general information, not legal advice. Have a property lawyer read your agreement before you sign.