Example Data Table
| Scenario |
Sell Price |
Repair Cost |
Success Chance |
Life Months |
Suggested Decision |
| Lab motor with bearing damage |
900 |
520 |
88% |
36 |
Repair likely works |
| Old appliance with heat damage |
250 |
460 |
55% |
12 |
Sell likely works |
| Precision instrument with calibration issue |
1800 |
740 |
80% |
30 |
Check risk first |
Formula Used
Downtime cost = downtime hours × hourly loss.
Total repair cost = repair quote + diagnostic cost + parts cost + transport cost + downtime cost.
Service value = expected life in months × (monthly use value + monthly energy saving).
Adjusted repair benefit = condition factor × (repaired market value + service value + warranty value).
Expected repair value = success probability × adjusted repair benefit + failure probability × failed repair salvage − total repair cost − risk cost.
Sell value = current sell price.
Decision margin = expected repair value − sell value.
If the margin is positive, repair has the stronger expected value. If the margin is negative, selling has the stronger expected value.
How to Use This Calculator
Enter the present selling price of the damaged asset. Add the likely market value after repair. Enter the repair quote, parts cost, diagnostic cost, transport cost, and downtime cost details.
Next, add the repair success chance, repeat failure risk, expected life, monthly value, energy saving, warranty value, and replacement cost. Use the condition rating to reflect wear, fatigue, corrosion, vibration damage, heat damage, or other physical limitations.
Press the calculate button. The result appears above the form and below the header. Use the CSV or PDF buttons to save the result.
Repair or Sell Decision Guide
A damaged machine, vehicle, instrument, or appliance often still has usable physical value. The hard question is whether repair converts that value into reliable service, or whether selling now protects cash and time. This calculator treats the choice as an expected value problem. It combines repair cost, resale price, remaining life, downtime, uncertainty, and efficiency changes.
Why Physics Matters
Physics enters through performance loss, energy use, wear, and reliability. A repaired device may consume more energy than a newer option. It may also fail again because fatigue, heat, friction, vibration, corrosion, or impact damage remains in the system. The calculator converts those effects into money so different choices can be compared on one scale.
Expected Value Method
The repair option is not judged only by the quoted repair bill. It includes diagnostic cost, downtime cost, future risk, operating savings, expected service months, and the chance that the repair succeeds. A high repair bill can still be sensible when the repaired value and remaining life are large. A cheap repair can be poor when failure probability is high.
Reading the Result
The result shows expected repair value, immediate sell value, decision margin, break-even repair cost, and replacement gap. A positive margin supports repair. A negative margin supports selling. A small margin means the decision is sensitive. In that case, check the repair quote, condition rating, market value, and risk assumptions before acting.
Practical Use
Use realistic numbers. Do not enter an optimistic resale value unless buyers actually pay that amount. Include transport, inspection, parts, labor, and lost work time. For technical equipment, include calibration and safety testing. For vehicles or motors, include fuel or energy changes. For assets with safety risk, the financial result should not override safe operation.
Assumption Check
Small inputs can change the answer. Test a low, normal, and high repair quote. Then test a lower success probability. This creates a useful range instead of one fragile answer. When the repaired asset must meet strict load, accuracy, pressure, or speed demands, add a safety allowance. If the repair only restores appearance, but not performance, reduce the repaired market value. Document every assumption, because better records improve repeat repairs and resale negotiations later too.
FAQs
1. What does this calculator compare?
It compares the expected value of repairing an asset with the cash value of selling it now. It includes cost, risk, service life, downtime, and resale impact.
2. Why is repair success probability important?
A repair quote is not enough. If success is uncertain, the expected value falls. This helps model failed repairs, repeated faults, and hidden damage.
3. What is condition rating?
Condition rating adjusts the repaired benefit. A lower rating reflects wear, fatigue, corrosion, heat damage, vibration damage, or poor remaining performance.
4. What should I enter as monthly use value?
Use the monthly value you gain from using the asset. This may include saved rental cost, production benefit, work value, or avoided replacement use.
5. Does the calculator include energy savings?
Yes. Monthly energy saving is added to the service value. This is useful for motors, appliances, pumps, vehicles, and electrical equipment.
6. What does decision margin mean?
Decision margin is expected repair value minus sell value. A positive number supports repair. A negative number supports selling.
7. Can this replace professional inspection?
No. It is a financial and physics-based estimate. Use expert inspection for safety, structural damage, electrical faults, and pressure or load systems.
8. Why include downtime cost?
Downtime can be expensive. Lost work time, rental substitutes, delayed production, or missed use can make a repair less attractive.