Short answer: To compare two apartments fairly, turn both into the same units. Divide the all-in price by RERA carpet area, add ten years of maintenance per carpet sq ft, then score what money can't fix: approvals, layout, surroundings and delivery risk. A higher headline rate can still be the cheaper flat per square foot you use.
- Carpet area is the common unit. RERA defines it in s.2(k), and the agreement must state it.
- Use the all-in price: add parking, club and deposits before you divide.
- Running costs can flip the result. In our example, the flat that wins on price loses after ten years of maintenance.
- A near-tie on money means decide on risk and fit.
- Our PAIRS scorecard: price, approvals, interior, running costs, surroundings.
Two shortlisted flats rarely come with figures you can compare directly. One quotes super built-up area, the other includes parking, one is ready and one is three years away. Here's how to put them on one sheet in Bengaluru.
What numbers do you need from each seller?
Ask each seller by email for:
- RERA carpet area for your unit, not the unit type.
- Balcony and terrace area, listed separately.
- Super built-up area, if that's how the price is quoted.
- The full cost sheet: base, floor rise, parking, club, deposits, maintenance advance.
- The RERA registration number and completion date.
- The maintenance rate and what it's charged on.
Carpet area under s.2(k) excludes external walls, service shafts and exclusive balconies but includes internal partition walls (RERA Act). Our carpet area explainer goes further.
How do you compare price fairly?
Two formulas do most of the work:
- Loading = (super built-up − carpet) ÷ carpet
- All-in price per carpet sq ft = everything you pay the seller ÷ carpet area
Stamp duty and registration (about 7.6% inside the GBA) scale with price, so they don't change which flat is cheaper. GST does, if only one flat is under construction; see our full cost guide. Our hidden costs page lists the extras to ask about.
Worked example 1: the higher rate that's cheaper
Illustrative figures for two ready flats.
| Flat A | Flat B | |
|---|---|---|
| Super built-up | 1,250 sq ft | 1,180 sq ft |
| Carpet | 900 sq ft | 920 sq ft |
| Loading | 38.9% | 28.3% |
| Quoted rate (super built-up) | ₹9,500 | ₹10,000 |
| Base price | ₹1,18,75,000 | ₹1,18,00,000 |
| Parking | Included | ₹3,00,000 |
| All-in price | ₹1,18,75,000 | ₹1,21,00,000 |
| Per carpet sq ft | ₹13,194 | ₹13,152 |
B quotes ₹500 more per sq ft and charges for parking, yet costs ₹42 less per square foot you can use, because its loading is lower.
Worked example 2: add ten years of maintenance
Now add maintenance, at assumed rates charged on super built-up area: ₹4 a sq ft for A and ₹5 for B. Ask each project for its real rate.
| Flat A | Flat B | |
|---|---|---|
| Monthly maintenance | ₹4 × 1,250 = ₹5,000 | ₹5 × 1,180 = ₹5,900 |
| Ten years (no increases) | ₹6,00,000 | ₹7,08,000 |
| Per carpet sq ft | ₹667 | ₹770 |
| Price plus maintenance per carpet sq ft | ₹13,861 | ₹13,922 |
The lead flips to A by ₹61 a sq ft, about 0.4%. That's a tie in practice, so the decision moves to the things below.
What should you compare beyond money?
- Approvals and delivery risk. Read both RERA pages with our project review method. If one is under construction, price the wait with our under-construction questions.
- Interior. Room sizes, wasted corridor space, light, cross-ventilation, which walls you share.
- Surroundings. Your commute at peak hour, schools, water source, flood exposure, approach road.
- Affordability. Run both all-in prices through our total cost calculator and our EMI-to-income check.
The PAIRS scorecard (our framework)
Score each flat from 1 to 5 on each line, multiply by the weight, add up, and divide by 5 for a score out of 100. Change the weights to suit you, but set them before you score.
| Factor | Weight | Flat A | Flat B |
|---|---|---|---|
| P: Price per carpet sq ft, all-in | 30 | 4 | 4 |
| A: Approvals and delivery risk | 25 | 3 | 4 |
| I: Interior layout and light | 15 | 3 | 4 |
| R: Running costs | 10 | 4 | 3 |
| S: Surroundings and commute | 20 | 4 | 3 |
| Score out of 100 | 72 | 74 |
A two-point gap is close. Treat anything under five points as a tie and visit both again at peak hour before you decide.
Side-by-side checklist
- [ ] Carpet area for each unit, in writing
- [ ] Full cost sheets, with every extra
- [ ] Loading and all-in price per carpet sq ft worked out
- [ ] Maintenance rate and basis for each
- [ ] Both RERA pages read; dates and extensions noted
- [ ] GST and waiting costs added if one is under construction
- [ ] PAIRS weights set before scoring
- [ ] Peak-hour visit to both
Frequently asked questions
Divide each all-in price by its RERA carpet area, add running costs per carpet sq ft, then score approvals, layout and surroundings with fixed weights.
Carpet area. It's defined in s.2(k) of the RERA Act and must be in the agreement, while loading on super built-up area varies from project to project.
Loading is (super built-up − carpet) ÷ carpet. A 1,250 sq ft super built-up flat with 900 sq ft carpet has 38.9% loading.
Not the ranking, because both scale with price. GST can, if one flat is under construction and the other is ready.
Add GST, rent and pre-EMI interest until possession, plus a delay buffer, to the under-construction price before you compare.
Yes. Over ten years it can add several hundred rupees per carpet sq ft and flip a close result, as in our example.
Treat a gap under five points as a tie. Visit both at peak hour, talk to residents, and let approvals and risk break it.
Yes, but weight surroundings and commute higher, and check guidance values and water sources for both areas.
Sources
Checked 19 Oct 2026.
- Real Estate (Regulation and Development) Act 2016, ss.2(k), 13, K-RERA copy: https://rera.karnataka.gov.in/resources/staticpage/Real_Estate_Act.pdf
- K-RERA project search: https://rera.karnataka.gov.in/viewAllProjects?language=en
- IGR Karnataka, Table of Registration Fees: https://igr.karnataka.gov.in/storage/pdf-files/RegistrationFee.pdf
- GST Council, FAQ on real estate: https://www.gstcouncil.gov.in/sites/default/files/2024-02/faq-real-estate-sector.pdf
