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Rent vs buy, run on your actual numbers instead of a vibe
Everyone has an opinion about renting versus buying. Run it on your real numbers, in your real market, with the costs people forget.
The prompt — copy and run it
You are a housing analyst with no stake in the outcome. Do NOT tell me buying is 'throwing money away' or that renting is 'dead money' — both are slogans. Run the comparison on the numbers I give you. Produce: A) THE FULL COST OF BUYING — not just the mortgage payment: property taxes, insurance, HOA/service charges, maintenance (use a stated assumption as a % of value and say it's an assumption), closing costs amortized over my realistic holding period, and the opportunity cost of the down payment (what that capital would otherwise earn — state the assumed return and flag it as an assumption). B) THE FULL COST OF RENTING — rent, expected annual increases (state the assumption), renter's insurance, and what I'd actually do with the money I didn't put down (be realistic: if I'd spend it, say so — the invest-the-difference argument only works if I actually invest the difference). C) THE BREAK-EVEN — how many years I must stay for buying to beat renting on MY numbers. Show the working. This is the number that decides it. D) THE THINGS THAT AREN'T IN THE MATH — flexibility to move, the cost of a forced sale in a bad market, the real value of not having a landlord, and the stress cost of maintenance. Name them, don't price them. E) WHAT WOULD CHANGE THE ANSWER — the two or three inputs my conclusion is most sensitive to, and how far each would have to move to flip it. Inputs: [PURCHASE PRICE + DOWN PAYMENT + RATE + TERM] · [PROPERTY TAX + INSURANCE + HOA] · [COMPARABLE RENT] · [HOW LONG I REALISTICALLY STAY] · [WHAT I'D DO WITH THE MONEY IF I DIDN'T BUY] Rules: Educational only, not financial advice. Do not invent current mortgage rates, tax rules or market forecasts — use ONLY the numbers I provide, and where I haven't given you one, ask rather than assume. Label every assumption explicitly and show the arithmetic so I can check it. Do not predict house prices. Mark anything I must verify for myself rather than asserting it. Never paste confidential, client, medical, or personally identifying information into a consumer AI tool, and don't ask me for any.
How to use this prompt
- Copy the full prompt above with the Copy button.
- Fill in your inputs. Replace each bracketed placeholder with your specifics:
[PURCHASE PRICE + DOWN PAYMENT + RATE + TERM][PROPERTY TAX + INSURANCE + HOA][COMPARABLE RENT][HOW LONG I REALISTICALLY STAY][WHAT I'D DO WITH THE MONEY IF I DIDN'T BUY] - Paste into ChatGPT, Claude, or Gemini and run. Read the reality guardrail below before you act on the output.
Why this prompt works
The rent-vs-buy decision is usually made on slogans and lost on the costs nobody counts — maintenance, closing costs amortized over a too-short holding period, and the opportunity cost of the down payment. Forcing an explicit break-even year, with every assumption labelled and the sensitivity named, converts a belief into a number you can actually check.
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Subscribe free → Read a sample issueFrequently asked
When should I use this prompt?
Everyone has an opinion about renting versus buying. Run it on your real numbers, in your real market, with the costs people forget.
Why does this prompt work?
The rent-vs-buy decision is usually made on slogans and lost on the costs nobody counts — maintenance, closing costs amortized over a too-short holding period, and the opportunity cost of the down payment. Forcing an explicit break-even year, with every assumption labelled and the sensitivity named, converts a belief into a number you can actually check.
What mistake does this prompt help you avoid?
Models parrot 'renting is dead money' and invent current rates and price forecasts. Restricting the model to the user's own numbers + labelled assumptions + shown arithmetic is the guardrail.
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