15 Things to Check Before Buying a Flat From a Builder

Buying a flat is probably the single largest purchase most people make in their lifetime and in India, where project delays and paperwork disputes still make regular headlines, it's also one of the easiest purchases to get wrong. A well-lit show flat, a persuasive sales team, and a "limited period" discount can make it tempting to sign on the spot. But the difference between a smooth homeownership experience and years of frustration usually comes down to a handful of checks done before you pay your booking amount, not after.

Here are the 15 things worth verifying before you buy a flat from any builder, whether it's your first home or your fourth.

Why Due Diligence Matters More Than the Brochure

Brochures are marketing documents, not legal ones. What actually protects you is what's on paper: the RERA registration, the builder-buyer agreement, the approved building plan, and the payment schedule. Since the Real Estate (Regulation and Development) Act, 2016 (RERA) came into force, buyers have far more legal protection than a decade ago but that protection only works if you know what to check and where to look. A few hours of due diligence now can save you the far more expensive, stressful process of fighting for possession, refunds, or repairs later.

The 15-Point Checklist

RERA registration number. Projects larger than 500 sq. m, or with more than 8 units, must be RERA-registered. Verify the number independently on your state's RERA website it will show the promised possession date, sanctioned plans, and any complaints on record.
Title deed and ownership chain. Confirm the developer legally owns the land, or holds clear development rights, with no unresolved disputes. A property lawyer can trace the chain of title through previous sale deeds to rule out a break in ownership.
Encumbrance certificate. Available from the sub-registrar's office, this confirms the land is free of loans, mortgages, or legal claims a basic but essential check before any money changes hands.
Approved building plan and layout. Compare the plan approved by the local development authority against what's actually being built. Unauthorised extra floors or deviations are a common source of demolition orders and delays years later.
Land use and zoning clearance. Verify the land is zoned for residential use, with environmental, fire, and municipal clearances in place. Improperly converted land can cause legal trouble long after you've moved in.
Carpet area, not super built-up area. RERA requires builders to sell on carpet area usable floor space within the walls rather than the inflated super built-up figures common before 2016. Get the exact figure in writing; it affects both GST and real value.
Occupancy Certificate (OC) and Completion Certificate (CC) status. The CC confirms construction is finished as approved; the OC confirms the building is safe to live in. A "ready to move" flat without an OC in hand is worth questioning closely ask when it's expected, in writing.
The builder's track record. Look at projects actually delivered, not just launched, and how close to schedule. Visit a completed project, speak to residents, and ask how defects or delays were handled past behaviour predicts your own experience.
Payment schedule linked to construction stage. A construction-linked plan instalments tied to milestones like foundation, slab, and finishing protects you far better than one that front-loads payment. Be wary of builders demanding a disproportionate upfront amount.
GST and other taxes. Under-construction flats attract 1% GST (affordable housing, up to ₹45 lakh) or 5% (other units), without input tax credit. Ready-to-move flats with an OC are GST-exempt. Confirm which applies and check it's reflected correctly in your cost sheet.
Amenities, in writing. Clubhouses and gardens photograph well in brochures, but only what's named in the agreement is guaranteed. If a specific amenity matters to you, confirm it's part of the sanctioned plan.
Parking allocation. A common post-possession dispute. Get your specific slot, or its allotment basis, documented in the agreement and confirm whether it's included in the price.
Maintenance and society formation terms. Understand who manages the property until the Resident Welfare Association forms, what maintenance costs will be, and how the corpus fund and handover work. Vague clauses here cause frequent disputes.
Possession date and delay-penalty clause. RERA mandates compensation for delayed possession, but the date and terms should still be explicit in your agreement, not a vague "reasonable time" clause. Confirm what interest applies for each month of delay.
Litigation check and bank loan approval. Search the builder's name in consumer court and RERA complaint records. Check which banks have approved loans for the project lenders conduct their own due diligence, so approval from multiple banks is a reassuring sign.

A Quick Red-Flag Checklist

No RERA number, or reluctance to share one
Pressure to pay in cash or outside official channels
Verbal promises that aren't reflected in the agreement
A history of delayed or stalled projects
Vague or repeatedly shifting possession dates
Heavy upfront payment demands before any visible construction

Two or more of these should be treated as a reason to slow down and dig deeper, not a reason to move faster.

FAQs

What is RERA carpet area, and why does it matter? Carpet area is the actual usable floor space within a flat's walls, excluding wall thickness, balconies, and common areas. RERA mandates that pricing be based on carpet area so buyers can compare projects fairly, instead of the inflated super built-up figures builders commonly used before 2016.

Is it necessary to hire a lawyer before buying a flat? It isn't legally mandatory, but a property lawyer typically costs a small fraction of the transaction value and can catch title defects, ownership gaps, or unfavourable agreement clauses that are easy to miss without professional review.

What happens if a builder doesn't have RERA registration? Selling a project where RERA registration is mandatory without one is a legal violation. Buying into such a project leaves you with significantly weaker recourse if there are delays, defects, or disputes later.

How do I verify a builder's RERA number? Visit your state's official RERA website and search by project name, builder name, or registration number. The listing will show the promised timeline, sanctioned plan, and any complaints on record.

Before You Sign

None of these checks take more than a few hours, and together they can save years of legal and financial trouble. Developers with a genuinely clean record RERA-registered projects, transparent carpet-area pricing, and a track record of on-time possession rarely mind buyers asking these questions; if anything, they'll have the answers ready before you ask. Trehan Group has delivered residential and commercial projects across Gurugram, Sohna, Neemrana, Bhiwadi, and Alwar since 1989, with RERA-registered developments and documentation available at every stage of construction.