Maintenance Cost Calculator Formula

Understand the math behind the maintenance cost calculator. Each variable explained with a worked example.

Formulas Used

Estimate (% of Value)

pct_estimate = pct_method

Estimate (Per Unit)

unit_estimate = per_unit_method

Monthly Reserve (Higher)

monthly_reserve = (pct_method > per_unit_method ? pct_method : per_unit_method) / 12

Variables

VariableDescriptionDefault
property_valueProperty Value(USD)350000
maintenance_pctAnnual Maintenance Rate(%)1.5
num_unitsNumber of Units2
per_unit_annualPer-Unit Annual Budget(USD)2500
pct_methodDerived value= property_value * maintenance_pct / 100calculated
per_unit_methodDerived value= num_units * per_unit_annualcalculated

How It Works

Estimating Maintenance Costs

Two common methods for budgeting maintenance and repairs:

Percentage-of-Value Method

Annual Maintenance = Property Value x Rate%

Typical range: 1-2% of property value annually

Per-Unit Method

Annual Maintenance = Number of Units x Per-Unit Budget

Typical range: $1,500-$3,500 per unit per year

Use the higher estimate for conservative budgeting

Worked Example

A $350,000 duplex using 1.5% value rate and $2,500 per unit budget.

property_value = 350000maintenance_pct = 1.5num_units = 2per_unit_annual = 2500
  1. 01Percentage method: $350,000 x 1.5% = $5,250
  2. 02Per-unit method: 2 x $2,500 = $5,000
  3. 03Higher estimate: $5,250
  4. 04Monthly reserve: $5,250 / 12 = $437.50

Ready to run the numbers?

Open Maintenance Cost Calculator