The number one cause of renovation stress isn't bad contractors or difficult decisions — it's money running out before the project is done. Most homeowners underbudget, and here's why: they plan for what they want, not for what renovation actually costs.
This guide will help you build a budget that's realistic, complete, and has enough buffer so you're not scrambling when the unexpected happens — and it always does.
Start With the Full Scope, Not a Wish List
The first mistake people make is building a budget around a Pinterest mood board. Before you put numbers to anything, write down every single room and every single thing you want done in it. Be specific: "kitchen" is not a scope. "Hack existing cabinets, re-tile floor and splashback, new base and wall cabinets, new countertop, replace sink and tap" is a scope.
Once you have the full scope, you can price it properly. Vague briefs produce vague quotes — and vague quotes always go over budget.
The Line Items People Always Forget
These are the costs that catch homeowners off-guard because they're not in most renovation packages:
- Hacking and disposal fees: Removing old tiles, cabinets, and debris has to go somewhere. Budget S$1,500–S$4,000 for a full flat.
- Waterproofing: Every wet area — bathrooms, kitchen, yard — needs proper waterproofing. Skipping this is how you get leakage into your downstairs neighbour's ceiling. Budget S$800–S$2,000 per wet area.
- Electrical works: Modern homes need more power points than old flats have. Add EV charger provisions, USB sockets, and smart home wiring if relevant.
- Window and door replacements: Often overlooked until you realise the contractor quote doesn't include them.
- Curtains and blinds: A furnished home needs window treatments. Budget S$2,000–S$6,000 for a 4-room flat.
- Appliances: Fridge, washing machine, oven, dishwasher — these add up fast.
- Furniture: If you're starting fresh, furniture can easily cost more than the renovation itself.
The real cost of a renovation is almost always 20–30% more than the initial quote once you factor in changes, upgrades, and the items nobody quoted in the first place.
How Much Contingency to Set Aside
The industry standard advice is 10–15% contingency. For resale flats, we'd recommend 15–20%, because hidden issues behind walls and under floors are far more common in older units.
Common unexpected costs in resale flats include:
- Failed waterproofing that needs full hacking and redoing
- Old electrical wiring that doesn't meet current standards
- Hacked walls that reveal structural issues
- Damaged pipes inside walls discovered during tiling works
Keep your contingency in a separate account that you mentally treat as "not your money." You'll feel much less stressed if something unexpected comes up — because you're already prepared for it.
Getting an Accurate Quote
Never accept a quote that isn't itemised. You should be able to see exactly what you're paying for every major element. If a contractor gives you a single line "full renovation: S$50,000," ask them to break it down. If they can't or won't, they're hiding something.
Get at least three quotes for any project. Don't automatically choose the cheapest — understand why each quote is the price it is. A low quote often means lower-grade materials, fewer warranty provisions, or work that simply won't be done.
When to Spend More, When to Save
Spend more on: Waterproofing, electrical work, structural elements, carpentry (since built-ins are hard and expensive to redo later), and the kitchen if you cook seriously.
Save on: Decorative items, furniture (which can be upgraded later), feature walls (paint is cheap to repaint), and accessories.
The general rule: spend on the things that are hard and expensive to change after the renovation is done. Save on the things that are easy to swap out in a few years.