After Repair Value (ARV) Calculator
Estimate a property's after-repair value (ARV), the 70% rule max offer, potential profit and ROI for flipping.
輸入資料
計算結果
重點速覽：ARV = current value + renovation value added. Max offer = ARV x offer rule% - renovation cost (commonly 70%). Potential profit = ARV - max offer - renovation cost. Potential ROI = profit / (offer + renovation cost) x 100%. The 70% rule reserves ~30% for fees, commission, holding costs and profit.
計算公式
修繕後價值 ARV = 修繕前現值 + 修繕增值。
最高出價 = ARV × 出價規則% − 修繕成本。
潛在利潤 = ARV − 最高出價 − 修繕成本。
潛在投資回報率 = 潛在利潤 ÷ (最高出價 + 修繕成本) × 100%。
$$\text{ARV} = \text{修繕前現值} + \text{修繕增值}$$$$\text{最高出價} = \text{ARV} \times \text{出價規則\%} - \text{修繕成本}$$使用說明
- Enter the current value and the expected renovation value added.
- Enter the renovation cost and the offer rule (commonly 70%).
- View ARV, max offer, potential profit and ROI.
以現值 1,000,000、修繕增值 500,000 (ARV 1,500,000) 為例，不同修繕成本與出價規則下的結果。
| 修繕成本 | 出價規則 | 最高建議出價 | 潛在利潤 | 潛在 ROI |
|---|---|---|---|---|
| 250,000 | 70% | 800,000 | 450,000 | 42.86% |
| 250,000 | 75% | 875,000 | 375,000 | 33.33% |
| 400,000 | 70% | 650,000 | 450,000 | 42.86% |
| 100,000 | 70% | 950,000 | 450,000 | 42.86% |
理財情境案例
案例一：70% 規則如何守住利潤緩衝
投資者看中一個舊單位，估計現值 HK$1,000,000，翻新後 (換廚廁、地板、油漆) 可增值 HK$500,000，即 ARV = HK$1,500,000，預算修繕成本 HK$250,000。
按 70% 規則：最高出價 = 1,500,000 × 70% − 250,000 = HK$800,000。若以此價買入，潛在利潤 = 1,500,000 − 800,000 − 250,000 = HK$450,000，ROI = 450,000 ÷ (800,000 + 250,000) = 42.86%。
這 30% 的緩衝 (150 萬的 30% = 45 萬) 正是用來吸收印花稅、代理佣金、律師費與持有期間利息差餉等——在香港，物業成交的印花稅與代理費並不便宜，這個緩衝能避免利潤被雜費侵蝕殆盡。
案例二：估錯 ARV 或修繕成本的風險
同一物業，若投資者過於樂觀，把 ARV 高估到 HK$1,700,000、又低估修繕成本，按 70% 規則會算出更高的出價上限，容易買貴。
翻新完成後若市況轉弱、實際只賣到 HK$1,450,000，加上修繕超支到 HK$320,000，原本預期的利潤就會大幅縮水甚至虧損。ARV 是「預測」而非保證，成交價受市況、修繕質素與同區可比成交左右。
穩健做法：ARV 參考同區近期實際成交 (可查差餉物業估價署資料與成交紀錄)、修繕成本預留超支緩衝、並把印花稅等交易成本另行計入，寧可保守估算，避免因高估 ARV 而出價過高。
常見問題
Why the 70% rule?
The 70% rule is a flipping rule of thumb: cap your offer at 70% of ARV minus renovation cost, reserving ~30% for transaction fees, commission, holding costs and profit. If confident on value or able to cut costs, some investors raise it to 75% to win deals.
Is the ARV accurate?
ARV is an estimate from current value and expected uplift, not a guarantee. Actual value depends on market, renovation quality and comparable sales. Use recent local transactions, professional valuation and several scenarios, with a buffer against overpaying.
Does it include transaction fees and tax?
No. The 70% rule reserves a buffer but does not itemise stamp duty, agency commission, legal fees or holding-period interest and rates. Add these to confirm profit covers all costs.
For Hong Kong flipping, what extra costs apply?
The reserved buffer must cover Hong Kong-specific costs: Ad Valorem Stamp Duty (AVD) on purchase, and possibly Special Stamp Duty (SSD) and Buyer's Stamp Duty (BSD) if not a first-time buyer or for short holding; agency commission (~1% each side); legal fees; holding-period mortgage interest, management fees, rates and government rent; and selling commission. Short-term flips can trigger heavier stamp duty — check applicable rates first, as these eat into profit.
70% or 75% rule?
Depends on confidence and cost control. 70% is conservative (30% buffer) — good in uncertain markets or for beginners. 75% wins more deals but lowers profit and ROI — for confident veterans who can control renovation and holding costs. Start at 70% for a safety floor, then fine-tune by project confidence, keeping a buffer for surprises.
相關工具
參考資料
內容審核：香港計算器財經團隊。計算邏輯與公式參考香港金融管理局（HKMA）及投資者及理財教育委員會（IFEC）之個人理財計算指引，結果僅供參考，實際以相關機構公佈為準。