Buying an under-construction flat in Bengaluru means paying today for something that does not exist yet, sometimes for five years. That is a reasonable thing to do, and it goes wrong in a small number of predictable ways. This is the checklist we actually run before we let anyone book — nine things, in the order that saves you the most money.

Before you pay anything

Four checks, and all four are free. Do them in this order, because each one can end the conversation and save you the next.

1. Verify the RERA registration for your phase. Not the township, not the project name — the specific phase your unit sits in. Large developments register phase by phase and finding the project in the portal proves nothing about your tower. The Karnataka portal holds over 10,492 registered projects and is free to search. Here is how, and it genuinely takes five minutes.

2. Read the declared completion date. The date filed with the regulator is the one with consequences attached. The date in your agreement comes second. The date a sales executive says out loud is worth nothing, and nobody will remember that conversation in 2031.

3. Check the promoter entity. Compare the name on the RERA filing against the name on your agreement. Large builders develop through separate entities per project, which is normal — but the two should match.

4. Look at the complaints register. The portal carries complaint status across 13,718 registered complaints plus the authority’s orders. A pattern of orders against a promoter is public and almost nobody checks it.

Work out what it actually costs

The price on the list is not the money that leaves your account. Correct for that before you decide anything.

5. Add the statutory charges. GST runs at 5% on under-construction property. Stamp duty is 5% above ₹45 lakh, registration is 2% since 31 August 2025, and cess adds roughly another half a per cent. Together that is about 13%, and none of it is financeable. A ₹1.37 Cr flat registers at ₹1,54,26,200. The full working is in our cost breakdown.

6. Price the wait. If you are renting at ₹32,000 a month, five years is a little over ₹19 lakh that buys you nothing, on top of EMIs on whatever has already been disbursed. Multiply your own rent by the months to handover and put that number next to the price. Almost nobody does this in a sales office.

Read the payment plan properly

7. This is the most underrated line in the whole agreement, and it can be worth several lakh.

A construction-linked plan releases money as the building rises. Your bank disburses in stages and you service EMIs on a growing balance for years before you have a key.

A back-loaded plan — something like 20/20/60, where 60% falls due only at possession — delays most of the borrowing to near handover. On a large purchase, that difference in interest paid before you move in is real money you simply never spend.

Neither is automatically better. A back-loaded plan means a larger sum due at the end, which you need to be certain you can raise. The point is to read it and price it, rather than treating the payment schedule as boilerplate that comes after the important decisions.

Ask for the schedule in writing with dates and percentages before you book, and work out what you will have paid by each year. If a developer will not produce that, it tells you something.

At handover, before you sign

Possession day is a document exchange, not a key ceremony. Treat it as one.

8. Get the occupancy certificate, naming your tower. An OC confirms the building is fit and legal to occupy. A completion certificate confirms it matches the approved plan — they are different documents and the OC is the one that matters. Watch for a partial OC that covers some towers and not yours: a developer can truthfully say “we have the OC” while your block is not on it. Ask to see the document and read which blocks it names. We set the difference out in occupancy certificate vs completion certificate.

A missing OC is not just untidy paperwork. It affects your GST position, makes resale harder because your buyer’s bank will ask for it, and complicates getting the Khata and permanent utility connections.

9. Settle the Khata. On an under-construction purchase the Khata follows completion and assessment, so there is nothing to check when you book. At handover, get the Khata details or a written commitment on when the transfer happens and who is doing it. Our e-Khata walkthrough shows what a genuine certificate looks like and which field to read first.

And take a signed snag list with dates against each item. Verbal assurances about the tiling evaporate once the site team moves on.

The question underneath all nine

Every check above assumes you should be buying under construction at all, and for a lot of people the honest answer is no.

If you need a home within two years, this category does not work. A 2031 handover cannot be negotiated shorter, and a good agent tells you that rather than working around it — we go through the arithmetic in what a 2031 possession actually costs.

A ready flat costs more per square foot and gives you no GST, a Khata you can read today, an OC that either exists or does not, and a home this year. That premium is often smaller than the rent and GST you avoid.

Under construction earns its place when you have somewhere comfortable to live, your plan survives a two-year delay, and you are placing capital rather than solving a housing problem. If all three are true, run the nine checks and buy with confidence. If any one is false, the checklist will not save you, because the problem is the category rather than the project. Compare what each budget reaches in what ₹1.5 crore buys on Sarjapur Road, and see the listings for what is currently selling.