Rome — complete worked example

A 90 m² apartment costs €5,188 × 90 = €466,920, so the required 20% down payment is:

€466,920 × 20% = €93,384

The couple earns €4,370 net per month and saves 30% of that income:

€4,370 × 30% = €1,311 per month

Saving for the down payment

During the saving phase, the accessible savings account earns 0.9% net per year. The equivalent monthly rate is:

0.9% ÷ 12 = 0.075% per month

Each month, the balance is updated as follows:

New balance = previous balance × 1.00075 + €1,311

At the end of each year, the accumulated accessible balance is transferred into a one-year term deposit. When the previous term deposit matures, it earns 1.4% net annual interest. The matured amount is then combined with the new savings and reinvested.

The approximate accumulated balances are:

• After year 1: €15,797.06
• After year 2: €31,815.27
• After year 3: €48,057.74
• After year 4: €64,527.61
• After year 5: €81,228.05

During the following 10 months, the couple accumulates another €13,154.33 in the accessible savings account.

At that point, the available amount is:

€81,228.05 + €13,154.33 = €94,382.38

This exceeds the required down payment of €93,384, so the target is reached after 5 years and 10 months.

Under the model, the current term deposit is redeemed early. Its interest for the incomplete term is forfeited, meaning that only the €81,228.05 principal is counted. Any amount above the exact required down payment is ignored when calculating the mortgage.

Mortgage phase

After paying the 20% down payment, the remaining mortgage principal is:

€466,920 − €93,384 = €373,536

The couple pays 48.125% of its combined net monthly income toward the mortgage:

€4,370 × 48.125% = €2,103.06 per month

The mortgage carries a constant annual interest rate of 3.25%, equivalent to:

3.25% ÷ 12 = 0.270833% per month

During the first month, the interest charged is approximately:

€373,536 × 0.270833% = €1,011.66

The remaining part of the monthly payment reduces the principal:

€2,103.06 − €1,011.66 = €1,091.40

After the first payment, the outstanding balance is therefore approximately:

€373,536 − €1,091.40 = €372,444.60

As the outstanding principal falls, the interest portion of each payment gradually decreases and the principal-repayment portion increases.

The mortgage is fully repaid after approximately 243 monthly payments, or 20 years and 3 months.

Over the full mortgage period:

• Mortgage principal: €373,536
• Total interest paid: approximately €136,495
• Total mortgage payments: approximately €510,031

Final Result

5 years 10 months saving + 20 years 3 months repaying = 26 years 1 month in total

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Sources:

Full post methodology: https://citycostatlas.com/methodology/03aug2026post/

Instagram: https://www.instagram.com/citycostatlas/

1. Number of tourists grew 525% year on year (5.25x YoY)

2. Number of residents increased by 15.4% ( mostly low wage service workers to service tourists like cab drivers, hotel staff etc)

3. No new hospitals, no expansion of housing (Airbnb's take out supply), no expansion of roads and sidewalks, no expansion of electric grid, no mass transit system

How to solve this issue

1. Higher fines of tourists indulging in anti-social behavior (€2000 per offense vs €200, €500 for roaming around shirtless vs €20).

If you can't pay, immediate removal order for next day after shaking them for every cent they have and then bye bye.

2. Introduce nightly tax on tourists from Airbnb short let to hotel - many cities do that.

3. Increase VAT on tourist, if you're a resident show identification to avoid the tax or file a tax return if your card is under process. Another way could be the government returns it to you after your employer uploads FS3s and then you claim it via Revolut/bank statements or physical invoices. I hate the digital Euro but this could also make it easier.

4. Tourist vs non-tourist price tiers for cab rides- do a kyc to prove you're a resident, tourist pay 5% surcharge.

5. Ban on Airbnb and short lets unless it's owner occupied. Short lets must be for residents only if those listings were intended as apartments and not zoned for hotels.

Reinvest in infrastructure

1. Introduce light rail/tram/metro now.

2. Introduce proper zoning - draw a line where you can build up and densify and concentrate density over there and zone other areas where you can't build more than x floors like suburbs or specific streets.

3. Every new building must have underground parking for residents and dedicated temporary unloading zones underground with life access for heavy equipment, pallets etc.

4. More hospitals immediately.

5. Raise minimum wage to match actual inflation, this would force businesses to charge what is fair to reflect the current inflation and raise more money for the government.