Buying one property together with unequal money

A couple with different savings, friends pooling deposits, siblings, or a parent helping a child buy. Two of you or eight. Fill in the blanks and this works out each person’s ownership share, the monthly bill, what it costs when one of you leaves, and what a sale pays everybody. Every figure shows the arithmetic that produced it, so you can check it and so can the others. Nothing you type leaves this page.

The walkthrough is on. Each section explains what its numbers mean and where to find them. Turn it off at the top once you know your way around. Nothing here is advice about what you should agree; it describes what the choices mean so that the agreement you make is the one you meant.

Buying with other people? The Ledger keeps the record for the years after closing, and the kit states the rules, $19 →

The purchase

The loan is whatever the cash contributions do not cover.

Purchase price: The price in the contract, before any fees.
Closing costs: The one-off fees to complete the purchase: lender fees, title or attorney work, recording, and prepaid tax and insurance. They are commonly quoted as two to five per cent of the price. If you have a lender’s Loan Estimate, the total is on it.
Rate and term: From the lender’s quote. Thirty years is the usual US term; twenty-five is common elsewhere. The rate changes the monthly bill a great deal and the ownership shares not at all.

Purchase price
Closing costs
Mortgage rate per cent a year
Mortgage term years

The parties

Add or remove people as your arrangement requires.

Cash at closing: Everything that person pays before getting the keys: their part of the deposit plus their part of the closing costs. If one person pays all the closing costs, that is part of their cash.
Income: Only used if you divide the monthly bill by income. Leave it if you will not.
On the loan: Whether that person is a borrower on the mortgage. Lenders limit how many borrowers they will accept, so in a group of three or four some people often own a share without being on the loan. It matters for one of the share methods below.
Money put in since: Repairs or improvements one person paid for after closing. Tick the box under the register to show the column. Under “capital back first” it comes back to them before any gain is divided.

NameCash at closingIncome a year Put in sinceAgreed %On loan

Some of us have put in money since closing

The shares you have agreed

There is no single correct method. These four are the ones in common use. Pick the one you have agreed on; everything below follows from it, and the printed schedule records which one you chose.

Cash at closing: Shares follow the cash. Simple, and it ignores who is on the hook for the loan.
Cash plus the loan each carries: Treats the mortgage as money each borrower is putting in, in equal parts, because each borrower is usually liable for all of it. This pulls the shares toward equal when the cash is unequal, and gives a person who is not on the loan a smaller share than their cash alone would.
Equal parts: Everyone owns the same, whatever they put in. People who choose this often settle the cash difference separately, as a loan between themselves. That side arrangement is not modelled here.
Figures we agreed: Whatever you negotiated. The page records it and derives nothing.

These are economic shares. How they are written onto the title, and what happens if one of you dies, are questions for the attorney who drafts your agreement.

Ownership is set by

Cash at closing Cash plus the loan each carries Equal parts Figures we agreed

The monthly bill

Everything the property costs each month, and how you divide it.

Mortgage payment: Principal and interest, worked out from the rate and term above. In the early years most of it is interest; the part that is principal is what builds your capital.
Property tax: Set by your county or municipality and often collected monthly by the lender into an escrow account. The listing or the assessor’s website shows last year’s figure.
Insurance: Homeowner’s insurance, which the lender requires. Get a quote before closing rather than guessing.
Association dues: Condominium or homeowners’ association fees, if any.
Maintenance reserve: Money set aside each month for repairs rather than spent. A rule of thumb many people use is one per cent of the home’s value a year.
Dividing the bill: By ownership share means you pay in proportion to what you own. If you pay a different share of the bill than you own, the capital each person has put in drifts away from the ownership shares over time. Section G shows that drift, and “capital back first” is the sale method that respects it.

Property tax a year
Insurance a year
Association dues a month
Maintenance reserve a month

The bill is divided by

Ownership share Equal parts Income

One party leaves, or everybody sells

Both are worked at the same moment, so the loan balance is the same in each. Change the year or the value to see any other moment.

Loan balance: What is still owed after the payments made so far, from the lender’s repayment schedule. The page computes it; your lender’s statement will show the same figure.
Value: Either a growth guess or a real valuation or offer. Type a price to override the guess.
Equity: The value minus what is owed. It is the whole of what there is to divide.
A buyout: One or more people leave and those who stay pay them for their part. There are usually no agent costs, so the figure is a share of equity, not of sale proceeds. Tick more than one name to see several people leaving at once; those who stay divide the payment and their shares are re-based to add to one hundred. People leaving at different times are worked by running the page again with the new shares.
A sale: Selling costs come off first, commonly five to ten per cent of the price including agent commissions, then the loan is repaid, then the rest is divided.
Two ways to divide: “By ownership share” splits the proceeds in the agreed proportions and ignores who paid what along the way. “Capital back first” returns to each person what they have actually put in, then divides only the gain by share. They agree when everyone paid in proportion to their share, and diverge when they did not.

Years from closing
Property grows per cent a year
Selling costs per cent of price
Sale or valuation price nil uses the growth rate
Who is leaving one or more; at least one stays

Proceeds and buyouts are divided by

Ownership share Capital back first, then the gain by share

The case where a sale does not cover everyone’s capital, and what the stayers pay when one of you leaves, are the two rules the templates skip. The kit states both →

What each person has put in, year by year

Cash at closing, plus each person’s part of the principal repaid so far, plus anything put in since. This is what “capital back first” returns before any gain is divided.

Most disputes between co-owners come from this table. If the bill is divided by anything other than ownership share, the person paying more of the mortgage is building more capital than their share says they own. The last line shows the gap at the year you chose above. Neither method is right or wrong; the point is to see the gap before you sign, not after.

The page assumes everyone pays their share every month. The kit’s ledger records what was actually paid, year after year →

The ledger, with the schedule kit

An agreement is signed once. The money moves every month for years, and when the time comes to sell, or for one of you to leave, the question is what each person actually put in, not what the plan said. Nothing free keeps that record. The Ledger does, and applies the rules you chose to the real history. It comes with the Schedule Kit: the rules stated generally, including the two cases the templates we examined all skip, and the decisions your agreement has to make.

From the kit · Rule 4, when a sale does not cover everyone’s capital

“If Net Proceeds are less than the total of all Capital Contributions but not less than zero, each Party receives the same fraction of their Capital Contribution, that fraction being Net Proceeds divided by the total of all Capital Contributions. Under either method, if Net Proceeds are less than zero, the shortfall is a debt owed by the Parties in their Ownership Percentages.”

That case, and the re-basing of shares when one of you leaves, appeared in no agreement template or calculator we examined. The kit states both, with their choices and worked examples, alongside five plainer rules and fifteen decisions to settle before anyone drafts anything.

The Ledger, a spreadsheet. Records what each person actually pays over the years, works out the principal part of every mortgage payment, and applies the sale and buyout rules to the real history, so a sale in year six is worked from facts rather than the plan. Plain formulas you can inspect; opens in Excel, Google Sheets, Numbers and LibreOffice.
The Schedule Kit, a PDF. Defined terms, the seven rules with their choices and worked examples, the decisions checklist, stress-test tables, and an exhibit sheet with a version identifier and a change log.

Agreement templates cost nothing to about $49 and set the legal terms; an attorney’s own draft costs more. This is not an agreement and does not replace one. It is the record and the arithmetic that sit beside whichever agreement you use. For comparison, one co-buying service sells a human-reviewed decision brief for $250.

$19 once. No account. Full refund within 30 days, no questions. Not yet on sale

The kit is being finished. The price will be $19 when it goes on sale. In the meantime, print the working copy free.

Words that come up

Deposit, or down payment: The cash paid toward the price at closing. The loan covers the rest.
Closing costs: One-off fees to complete the purchase. Separate from the deposit and paid in cash.
Principal and interest: Principal is the money borrowed; interest is the charge for borrowing it. Each payment pays some of both, mostly interest at first.
Amortisation: The schedule by which a loan is repaid in equal payments over its term. It is why the balance falls slowly at first and quickly at the end.
Equity: What the property is worth minus what is owed on it.
Escrow: An account the lender keeps to pay tax and insurance on your behalf, funded by part of each monthly payment.
Capital: On this page, what a person has actually paid in: cash at closing, their part of the principal repaid, and anything put in since.
Buyout: One owner leaving and being paid for their share by those who stay.
Tenants in common, joint tenants: Two common ways of holding title together. They differ in whether unequal shares can be recorded and in what happens when an owner dies. Which one fits is for your attorney.
Appreciation: The rise in value over time. The growth rate above is a guess at it; a valuation or an offer is a fact.