Big CopilotBig Ambitions wiki

How rent works

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Rent on a commercial building is not a number the game picks at random. It follows the floor area, the foot traffic at the door, and the district the building stands in.

What a listing charges

A rental listing states a rent per day and a deposit. The rent is billed daily for as long as you hold the lease. The deposit is paid once, when you sign.

The deposit is the larger number, and it is due the day you sign. For a shop or an office it comes to about two months of rent; for a warehouse, about three. Big Copilot estimates it from the rent and shows it in the location finder as Upfront, so a cheap-looking building that you cannot afford to open is visible before you take it.

A residential listing adds a charge for appliances on top of those two.

Those numbers are the game's own. Big Copilot reads them; it does not set them.

The formula

For a commercial building the daily rent is:

rent per day = floor area × (30 + traffic index) × district rate

Floor area is the building's square metres and the traffic index is the foot traffic the game shows for that address. In an office building the result is multiplied by 1.033.

The district rate is the part the game never shows. These seven are what the leases give:

DistrictRate
Midtown0.02482
Hell's Kitchen0.01468
Murray Hill0.01020
Garment District0.00734
Lower Manhattan0.00621
The Hamptons0.00568
Industry City0.00566

How well it holds

The rates were fitted on 15 September 2026 against 48 player leases across three characters, on game build 3675. Every one of those leases matches the formula to within 0.6%, which is integer rounding.

Residential leases do not follow it. A home is shown with no estimate rather than a wrong one.

A game patch can rebalance rents. That is why the date is stated: if the numbers stop matching what a lease charges, the fit is what went stale, not the lease.

Where Big Copilot uses it

The map shows this estimate on every building's card, so a vacant building can be compared with an occupied one before you sign anything.

The location finder ranks buildings by demand and traffic, not by rent. Rent is shown beside each candidate as a cost to weigh, and it does not move a building up or down the list.

Big Copilot's own fit, 15 September 2026: 48 non-residential leases across three characters on game build 3675, worst residual 0.6%. Not stated anywhere in the game's help.