Gross rent multiplier is what you can compute when you know a price and a rent and almost nothing else. Divide the price by the annual gross rent. A lower result means more scheduled rent per dollar of price. A higher result means the opposite. The multiplier is a sort key for a list of similar buildings. It is a bad final answer, because everything that happens between rent and cash is invisible to it.
Gross rent multiplier = price ÷ annual gross rent.
If you only have monthly rent, annual gross rent is that monthly figure times twelve, and you have already assumed the unit is occupied all year at that rent. That assumption is part of the screen. It is not a finding.
What you are allowed to put in the fraction
Use the price you would pay, including repairs required before the unit can be leased. Use rent you can support with a lease in place or with leased comps, not the flyer’s “estimated rent.” If three units are leased and one is vacant, do not silently put market rent on the vacant unit and call the total “gross.” Either show scheduled rent as it is, or show a second version that fills the vacancy and label it as a scenario. Mixing them is how a multiplier gets shopped.
Other income is a judgment. A strict gross rent multiplier uses rent. Laundry and parking can be added only if you are going to do that the same way for every property you compare, and only if the income is real. Inconsistent numerators make the sort meaningless.
The 1 percent rule uses the same two facts in monthly clothing. Monthly rent divided by price is the reciprocal of the multiplier, scaled by twelve. If you already ran one, you have run the other. Do not present both as independent evidence.
How a sort is supposed to work
Pull a set of listings or recent sales that match on the things the multiplier cannot see: unit count, rough age, and the same neighborhood, so taxes, insurance habits, and tenant demand are at least cousins. Compute the multiplier for each. The low end of that set deserves the first document request. The high end needs a reason — a better building, a lease below the rent you can document, a seller who priced a renovation that is not done — or it waits.
Solving the formula the other way, price = annual gross rent × a multiplier taken from real sales, is a rough value check. It is only as good as those sales. If you do not know the rents at the time of sale, you do not have a market multiplier. An asking multiplier on unsold listings is a description of hope. Say which one you used.
The Deal Analyzer will accept the rent and price you type and print screening math, including a gross rent multiplier built from those inputs. It cannot go get the comps. If you type the brochure rent, it will rank the brochure.
Everything the multiplier leaves on the table
Operating expenses. Two buildings with the same multiplier can differ by the tax bill after a sale, the insurance quote, association dues, and who pays the water. In a high-insurance or high-tax area, gross rent is a vanity number. The expense-stack worksheet is the next page, not an optional appendix.
Vacancy and concessions. A free month, a seller-paid utility, or a unit that sits empty between tenants means collected rent is below the gross you used. The multiplier treats the lease rate as if it arrived twelve times.
Condition. Deferred maintenance makes a multiplier look attractive because the price is lower and the current rent might still be in place. The roof, the sewer lateral, and the panels are not in the fraction. A low multiplier on a tired building is often the market charging you, in advance, for work you have not bid yet.
Financing. The multiplier does not contain a rate, a term, or a prepayment penalty. Cash flow can fail on a “good” multiplier and hold together on a “bad” one if the loans differ. Cap rate at least subtracts operating expenses before it looks at price. The cap rate guide is that next ratio, and it still ignores the loan. Neither one is cash in your account.
Legal use. A multiplier on rent from a unit the city does not recognize is a multiplier on income you may not be allowed to keep. Zoning and permits are not in the arithmetic. The pre-offer checklist puts that question before the offer, which is where it belongs.
A practical order that does not pretend the screen is diligence
Rank the list with the multiplier, using the same rent rules for every address. Throw out nothing permanently; set aside the ones that need a sentence of explanation. For the survivors, replace gross rent with a rent file and replace silence with bills: tax, insurance, utilities, dues, repairs, a capital reserve. Only then compute net operating income and a cap rate you can name as in-place or as documented change. Then add the loan you were quoted.
If a seller leans on a low multiplier, ask which rent and which price produced it, and whether expenses were ever part of the conversation. If they were not, the figure did its job: it started an argument about documents. It should not end one.
A worked identity with symbols, not a fake building
Let price be P and annual gross rent be R. The multiplier is P / R. If you are comparing two listings and you change R for only one of them — filling a vacancy on the first and not on the second — you changed the ranking by changing the rule. Write the rule at the top of the page: “in-place rent only” or “vacant units at leased-comp rent, labeled.” Then compute every address the same way.
If rent is wrong by a wide margin, the multiplier is wrong by the same margin in the other direction, because R is the denominator. That is why a portal estimate is dangerous here. It does not need to be wildly wrong to reshuffle which building you visit first. Correct the rent file before you correct the paint color in your head.
A multiplier also has no memory of a concession. One free month on a twelve-month lease means collected rent is eleven months, not twelve. If you ignore that, you are using a gross the tenant never pays. Note concessions beside R or reduce R and say you did. Do this for every lease in the set, or the building that “included a free month” will look cheaper than the building that simply charged less.
The glossary defines the multiplier in a few lines and warns that a result that looks normal in one city can be a mistake in another. There is no universal “good” multiplier on this page, because a universal number would be a fiction. Your set of comparable sales is the only range that counts, and only when you can show the rents.
This is education about a screening ratio. It is not an appraisal and not a recommendation to prefer a lower multiplier without reading the expenses.
Field notes
GRM ignores expenses, which is the entire joke in a high-insurance ZIP. Use it to sort a list of 40 addresses, then throw it away. Two houses with the same GRM can differ by $400/month once taxes and HOA show up. Replace GRM with the expense-stack worksheet before you talk price.