Aletheor Space
Aletheor Space · decision support
Rent, Buy or Share?
Make a clearer decision about the space you live in or work from.
Compare renting, buying and sharing a home or business space over the time you choose — and see how each option holds up if things change.
Upfront cash
What each option asks of you on day one.
Long-term cost
The full cost over your horizon, after money back.
Resilience
How your reserves cope if income falls or costs rise.
Educational estimates only. Nothing you enter leaves your browser.
How it works
Enter your situation
Your income, essential spending and the savings you could use. Then the main costs of each option.
Compare Rent, Buy and Share
See upfront cash, monthly impact, total cost and what is left in reserve — side by side.
Test it under stress
Check what happens if income falls, costs rise, rates change or you need to leave early.
Step 1
Choose your situation
Step 2
Your numbers
Start with the essentials. Everything else is optional and can stay closed.
Not sure where to start? Load a complete household example.
Essentials
Your household's monthly position before housing costs.
How long to compare.
Cash you could use within weeks without borrowing — not property, pensions or locked investments.
Funding and inflation (optional)
Repayable, so it does not count as your own money.
Your assumption, not a forecast.
Rent
Lease the space on your own.
Not already in the rent.
More costs and terms
Break date or lease end. Blank = leave any time.
Leave early or mark unsuitable
Blank = stay to the horizon.
Buy
Buy with a mortgage. Ownership costs are taxes, insurance, maintenance and service charges.
Tax, insurance, maintenance, service charge.
Enter price, down payment, rate and term to see the monthly mortgage payment.
Value, selling and mortgage details
Can be negative.
Leave early or mark unsuitable
Blank = stay to the horizon.
Share
Share space with others, e.g. a flat-share or co-working desk, for a monthly fee.
Not already in the rent.
More costs and terms
Break date or lease end. Blank = leave any time.
Leave early or mark unsuitable
Blank = stay to the horizon.
Labels only — all amounts are in one currency and nothing is converted.
Step 3 · Comparison
Over 5 years
All amounts in USD. Changing the currency changes labels only — no exchange-rate conversion. Based only on your inputs and assumptions — not a forecast.
Nothing to compare yet
Enter the required fields (marked *) for at least one option, or load the example.
Rent: incomplete — missing monthly amount.
Buy: incomplete — missing purchase price, down payment.
Share: incomplete — missing monthly amount.
Step 4
What if things change?
Each test changes some of your inputs and recalculates. These are illustrative assumptions you choose, not predictions.
- Income falls
- Less money coming in each month while spending stays the same.
- Space costs rise
- Rent, share fees, running and ownership costs go up.
- Interest rates change
- Only affects a variable-rate mortgage; fixed rates stay as entered.
- Property value changes
- Changes what a sale would bring back, and therefore Buy's equity.
- Early exit and fallback
- Leaving before the horizon, then renting or sharing until the end. Set it under each option's “Leave early” section.
Method
Assumptions and methodology
Short definitions sit beside each result above. The full method is here if you want it.
Formulas and assumptions
- Total cash paid = upfront costs + all monthly payments (rent, running costs, mortgage interest and principal, ownership costs) + exit costs.
- Money back = deposit refund, or for Buy: sale value minus mortgage still owed. Selling costs are counted once, as an exit cost.
- Estimated net equity = property value − mortgage still owed − selling costs − early-repayment fee (can be negative).
- Net occupancy cost = total cash paid − money back + upfront-loan costs + loan debt still owed. Lower is cheaper under these assumptions.
- Rent and fees step up once a year from month 13. Property value changes smoothly each month.
- Early exit: the chosen fallback (Rent or Share) runs from the exit month to the horizon. With no fallback the option is not ranked.
- Freedom Cost 'may be reduced' amount covers base rent only and excludes running costs.
- Space Stress Score (provisional, 0 = lower stress, 100 = higher): average of cost burden, cash margin, capital lock-up, shock runway and exit burden. Business cost burden uses cash flow before space costs; business cash margin uses cash inflow.
- Today's-money view divides each month's amount by (1 + inflation)^(month/12). All amounts are in one currency; no exchange rates or live data are used.
Limitations
- Growth rates, inflation, price drops and stress levels are assumptions you choose or illustrative defaults — not forecasts or established standards.
- Taxes, benefits, tax relief and local rules are not modelled unless you include them in your numbers.
- One currency only; no exchange rates or live market data.
Important
This is an educational estimate based only on the numbers you enter. It is not financial, tax, legal or mortgage advice, and it does not rank any option as "best".