Lettable area and units of different sizes
Total lettable area is the number of units multiplied by their average floor area. If you plan to offer different sizes, divide the combined area of all units by the total number of units. For example, ten 4 m² units, ten 8 m² units and ten 12 m² units provide 240 m² in total, averaging 8 m² per unit. Do not include access roads or the space between containers in the lettable area.
The cost of opening a Self Storage facility
Start-up costs cover land or site preparation, the total purchase cost of units, fencing, CCTV and a gate, plus design, paperwork and other initial expenses. Enter monthly lease payments separately under operating costs to avoid counting the same expense twice. The purchase amount covers all units and does not update automatically when you change their number or size. When gathering quotes, you may find our Self Storage manufacturer ranking useful.
Rental income and break-even occupancy
Monthly income equals lettable area × rent per m² × occupancy rate. Occupancy is the proportion of lettable space rented out, not the proportion of the site covered by containers. We subtract your entered monthly costs: lease payments, utilities, software, marketing and other expenses such as insurance or maintenance. Tax is calculated at your chosen percentage only on positive profit after operating costs; no tax is deducted when there is a loss. Break-even occupancy is the occupancy needed to cover operating costs before tax at the entered rental rate. Find systems for managing rentals in our Self Storage software directory.
Payback period and annual ROI
The estimated payback period is total start-up costs divided by positive monthly profit after operating costs and the calculated tax. Estimated annual profit is that monthly profit multiplied by 12. Annual return on investment (ROI) expresses this amount as a percentage of the initial investment. If profit after tax is not positive, the calculator displays “No payback”. The calculations assume constant costs, rent and occupancy from the start; they do not allow for the time needed to attract your first tenants.
How should you interpret the results?
The default values are an example scenario, not a manufacturer's quote or confirmation that an investment will be profitable. Compare several occupancy levels and enter your own costs. The displayed profit includes operating costs and a simplified tax calculation at your chosen rate, which defaults to 0%. This is not a calculation of actual tax liabilities: the model does not calculate VAT, tax reliefs or social insurance contributions. It also excludes financing, depreciation, seasonality and changes in rates over time. Enter all amounts on the same basis; do not mix VAT-exclusive and VAT-inclusive figures. For the next steps in planning your investment, read our eight-step guide to opening a Self Storage facility.
