Property ROI made simple: rental yield, costs and financing

Key points

• ROI (return on investment) shows a gain or loss as a percentage of the money invested. It describes an outcome; it does not forecast profit.
• Sale profit, annual rental yield and the return on your own cash after borrowing are three separate calculations.
• There is no universal double-digit benchmark. A sensible target depends on risk, financing, currency and how long you hold.
• Most misleading results come from inconsistent inputs, not from hard maths.

As of 23 March 2024 (source revised 6 January 2026). All amounts are the source's worked examples, not market figures. Tax rates and rules may have changed since, so please check the current position. General information only, not legal or tax advice.

Define what you are measuring

A percentage is only meaningful with a stated period, a clear cost base and a list of what is included. Used that way, it supports:

• Buying decisions: testing a price against expected income and costs, which remain assumptions until they happen.
• Reviewing performance: actual figures show what the investment earned or lost against its cost.
• Cash planning: a cash-flow budget shows when money is needed, something a single percentage cannot.
• Comparisons: like with like, meaning the same period, currency and treatment of debt, tax and transaction costs.
• Risk: run a lower-rent, higher-cost scenario. ROI on its own does not measure the chance of a loss.

The basic formula

ROI (%) = Net profit / Total investment cost × 100

Total investment cost covers the purchase and every cost assigned to the investment. Net profit is what remains after those costs.

Unlevered sale: an all-in cost of USD 150,000 and net sale proceeds of USD 180,000 give a profit of USD 30,000 and an ROI of 20%. That is the return over the whole holding period, not automatically per year, and any extra cost reduces it.

Three worked examples

Rental yield. Divide annual rental income after the stated operating expenses by the defined acquisition cost. USD 10,000 of annual operating income on USD 150,000 of total acquisition cost is about 6.67%, before financing and personal income tax, and excluding any change in value. Spell out vacancy, repairs, management and insurance.

Cash purchase with letting. Acquisition and improvements of USD 150,000, annual rent of USD 18,000 and stated operating expenses of USD 5,000 leave operating income of USD 13,000, an annual net rental yield of about 8.67% before personal income tax and with no borrowing. A fuller budget adds realistic vacancy and allowances for future replacements.

Financed purchase. A USD 500,000 home bought with USD 180,000 of your cash and a USD 320,000 loan. If the value rises to USD 600,000 and the loan balance is unchanged, your equity is USD 280,000, not USD 420,000. Equity divided by value is an equity ratio, not ROI. The USD 100,000 unrealised gain is about 55.56% of the initial cash, before interest, transaction costs, taxes and rental cash flow. It is neither an annual cash return nor a realised profit.

Other measures you will see

• Cash-on-cash return: annual pre-tax cash flow after operating costs and debt service, divided by the owner's cash invested. USD 12,000 on USD 180,000 is about 6.67%. Unrealised appreciation is excluded.
• Sale profit: proceeds and income less acquisition, improvement, holding and disposal costs as applicable. Fix the period and never count a cost twice.
• Net operating income (NOI): income less vacancy and operating expenses, before debt service and the owner's income tax. Capital expenditure and depreciation are handled separately.
• Capitalisation rate: annual NOI divided by purchase price or current value. Say which one you used. It ignores financing and is not a full total-return measure.
• Appreciation: a paper gain until you sell. Values can fall too, and a valuation pays no bills.
• Internal rate of return (IRR): reflects the timing of cash flows. It is the discount rate at which their net present value is zero, so it depends heavily on assumed payments and exit proceeds.

What moves the result

• Location: access to work, transport and services shapes who will want to live there. A sought-after address usually costs more, so demand alone does not mean a higher percentage return. That applies to a city flat as much as to a holiday home in Side.
• Condition and upkeep: a well-kept home may need less work now, but the price tends to reflect that. Budget for recurring maintenance and major replacements.
• Rent and expenses: use achievable rent, realistic occupancy and the full cost of lawful letting. A higher advertised rent does not necessarily mean more money kept.
• Market conditions: prices, interest rates, rents and resale demand change. Keep currency assumptions consistent and allow for inflation. More recent market figures are in our post on house prices in March 2026.

Common calculation mistakes

1. Only modelling the best case. Peak rent and a quick resale should never be the sole scenario.
2. Leaving costs out. Include transaction costs, vacancy, insurance, management, repairs and relevant taxes, and show what is excluded.
3. Weak comparisons. Asking prices and promised rents are not completed sales or collected income. Our newer guide to judging property prices shows how to assess an offer.
4. Skipping the right advice. Use an agent for market information and qualified legal, tax and technical advisers for their fields.

Strengthening your plan

None of these guarantees a return, but each makes the numbers more honest:

• Buy with a repair budget. A cheaper home needing work is not automatically worse, and a finished one is not automatically better value.
• Test the rent against comparable lettings and allow for empty months.
• Choose for the occupant. The location should suit the likely tenant or guest, not just be "popular".
• Spread risk with care. Different properties can still share currency, tourism and financing risks.
• Hold longer to spread transaction costs, while ongoing expenses and market risk remain.
• Treat developing areas cautiously. Future infrastructure and demand are assumptions until delivered; allow for delays and a slower resale.

Want to run the numbers on a specific home? Browse our current properties for sale. The Side Immobilien team in Side can gather the property details you and your advisers need. Contact us